• Hello!

    From Richard Hachel@21:1/5 to All on Sat Jan 18 10:34:58 2025
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about what
    complex numbers were, wondering if teaching them was so important and
    useful, especially in kindergarten where children are only learning to
    read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component" would
    not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative.

    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of
    Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things in different ways.

    Explanations: We ask Mrs. Martin how many students she has in her class,
    and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning class
    or the evening class (catch-up classes for adults), the answer will not be
    the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the two classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and -1, depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the product
    of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me): Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by setting (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula
    Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes:
    Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1, which
    gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the misunderstanding
    of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From sobriquet@21:1/5 to All on Sun Jan 19 02:53:29 2025
    Op 18/01/2025 om 11:34 schreef Richard Hachel:
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about what
    complex numbers were, wondering if teaching them was so important and
    useful, especially in kindergarten where children are only learning to
    read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component" would
    not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative.

    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things in different ways.

    Explanations: We ask Mrs. Martin how many students she has in her class,
    and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning
    class or the evening class (catch-up classes for adults), the answer
    will not be the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the two classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and -1, depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the
    product of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me): Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by setting (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes: Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1, which gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the
    misunderstanding of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians
    become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    If we define complex multiplication in the way you suggest instead of
    the conventional way, that would mean that the operation of conjugation
    would no longer be a homomorphism with respect to the field of complex
    numbers under multiplication.

    So conj(z1*z2) would not be equal to conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Sun Jan 19 07:41:39 2025
    Le 19/01/2025 à 02:53, sobriquet a écrit :
    Op 18/01/2025 om 11:34 schreef Richard Hachel:
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about what
    complex numbers were, wondering if teaching them was so important and
    useful, especially in kindergarten where children are only learning to
    read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component" would
    not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative.

    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of
    Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things in
    different ways.

    Explanations: We ask Mrs. Martin how many students she has in her class,
    and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning
    class or the evening class (catch-up classes for adults), the answer
    will not be the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the two
    classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and -1,
    depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the
    product of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me):
    Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by setting
    (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula
    Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form
    Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes:
    Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1, which
    gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the
    misunderstanding of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians
    become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    If we define complex multiplication in the way you suggest instead of
    the conventional way, that would mean that the operation of conjugation
    would no longer be a homomorphism with respect to the field of complex numbers under multiplication.

    So conj(z1*z2) would not be equal to conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    Thank you for your answer.

    But nevertheless, I continue to certify that there is an extremely fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Because as long as we do not know what i is worth, which can be BOTH equal
    to 1 or -1 in this imaginary mathematics, we must pose i²=-1.

    But once we pose i=1, it is no longer possible to say i²=-1; and in the
    same way, when we pose i=-1, it is no longer possible to say 1²=-1.

    It is necessary, at this instant where we have defined i (whether it is 1
    or -1 but defined at this instant, it is necessary to set Z=z1*z2 such
    that:
    Z=(a+ib)(a'+ib')=aa'+bb'+i(ab'+a'b) to have the correct result, otherwise
    the real part becomes very incorrect.

    You tell me: yes, but it does not work with the conjugate.

    Of course it does.

    If it does not work, it is because you make a sign error, and the computer
    does the same because it is not formatted on the right concept giving the
    right real part.

    Mathematical proof that Z(conj)=z1(conj)*z2(conj)

    We set:
    z1=16+9i
    z2= 14+3i

    Z (equation correct)=aa'+bb'-i(ab'+a'b)

    Z=251+174i.

    Let z1(conj)=16-9i and z2(conj)=14-3i

    Z(conj)=aa'+bb'+i(ab'+a'b)
    Z(conj)=(16)(14)+(-3)(-9)+i[(16)(-3)+(14)(-9)]
    Z(conj)=251-174i

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Sun Jan 19 07:51:22 2025
    Le 19/01/2025 à 02:53, sobriquet a écrit :
    Op 18/01/2025 om 11:34 schreef Richard Hachel:
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about what
    complex numbers were, wondering if teaching them was so important and
    useful, especially in kindergarten where children are only learning to
    read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component" would
    not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative.

    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of
    Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things in
    different ways.

    Explanations: We ask Mrs. Martin how many students she has in her class,
    and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning
    class or the evening class (catch-up classes for adults), the answer
    will not be the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the two
    classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and -1,
    depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the
    product of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me):
    Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by setting
    (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula
    Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form
    Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes:
    Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1, which
    gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the
    misunderstanding of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians
    become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    If we define complex multiplication in the way you suggest instead of
    the conventional way, that would mean that the operation of conjugation
    would no longer be a homomorphism with respect to the field of complex numbers under multiplication.

    So conj(z1*z2) would not be equal to conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    Thank you for your answer.

    But nevertheless, I continue to certify that there is an extremely fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Because as long as we do not know what i is worth, which can be BOTH equal
    to 1 or -1 in this imaginary mathematics, we must pose i²=-1.

    But once we pose i=1, it is no longer possible to say i²=-1; and in the
    same way, when we pose i=-1, it is no longer possible to say 1²=-1.

    It is necessary, at this instant where we have defined i (whether it is 1
    or -1 but defined at this instant, it is necessary to set Z=z1*z2 such
    that:
    Z=(a+ib)(a'+ib')=aa'+bb'+i(ab'+a'b) to have the correct result, otherwise
    the real part becomes very incorrect.

    You tell me: yes, but it does not work with the conjugate.

    Of course it does.

    If it does not work, it is because you make a sign error, and the computer
    does the same because it is not formatted on the right concept giving the
    right real part.

    Mathematical proof that Z(conj)=z1(conj)*z2(conj)

    We set:
    z1=16+9i
    z2= 14+3i

    Z (equation correct)=aa'+bb'+i(ab'+a'b)

    Z=251+174i.

    Let z1(conj)=16-9i and z2(conj)=14-3i

    Z(conj)=aa'+bb'+i(ab'+a'b)
    Z(conj)=(16)(14)+(-3)(-9)+i[(16)(-3)+(14)(-9)]
    Z(conj)=251-174i

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 12:04:05 2025
    Am 19.01.2025 um 08:51 schrieb Richard Hachel:

    But nevertheless, I continue to certify that there is an extremely fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Nope. i² = -1 was not invented/introduced by physicists, but by mathematicians.

    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we [...]

    i is neither 1 nor -1.

    Hint: If it were 1 or -1 we would get i² = 1 (in bot cases).

    .
    .
    .

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 12:09:12 2025
    Am 19.01.2025 um 12:04 schrieb Moebius:
    Am 19.01.2025 um 08:51 schrieb Richard Hachel:

    But nevertheless, I continue to certify that there is an extremely
    fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Nope. i² = -1 was not invented/introduced by physicists, but by mathematicians.

    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we [...]

    i is neither 1 nor -1.

    Hint: If it were 1 or -1 we would get i² = 1 (in bot cases).

    Of course, such a number does not exist in the real number field. But
    there is such a number in the complex number field:

    "In mathematics, a complex number is an element of a number system that
    extends the real numbers with a specific element denoted i, called the imaginary unit and satisfying the equation i² = -1; ..."

    See: https://en.wikipedia.org/wiki/Complex_number

    .
    .
    .



    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Sun Jan 19 11:37:17 2025
    Le 19/01/2025 à 12:04, Moebius a écrit :
    Am 19.01.2025 um 08:51 schrieb Richard Hachel:

    But nevertheless, I continue to certify that there is an extremely fine
    mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Nope. i² = -1 was not invented/introduced by physicists, but by mathematicians.

    Yes, I made a slip of the tongue.

    :))


    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we [...]

    i is neither 1 nor -1.

    I consider (I could be wrong) that this is a case where we do not know
    what i is worth, and we hesitate between two values.
    In short, that for the moment, i is "imaginary", and can take two values.
    It is neither 1 nor -1, but both at the same time potentially, and its
    square is (1)(-1)=1.
    Which means that z is also a number and that it can take two values
    ​​at the same time.
    Example z=16+9i gives z=25 AND 7 at the same time.
    See the example of the Plougastel college where we do not know which class
    we are talking about because the class is occupied by both 25 students in
    the morning and 7, who come to the evening class.

    Hint: If it were 1 or -1 we would get i² = 1 (in bot cases).

    It' that I said.

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From sobriquet@21:1/5 to All on Sun Jan 19 15:09:00 2025
    Op 19/01/2025 om 08:51 schreef Richard Hachel:
    Le 19/01/2025 à 02:53, sobriquet a écrit :
    Op 18/01/2025 om 11:34 schreef Richard Hachel:
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about what
    complex numbers were, wondering if teaching them was so important and
    useful, especially in kindergarten where children are only learning
    to read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component"
    would not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative.

    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of
    Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things
    in different ways.

    Explanations: We ask Mrs. Martin how many students she has in her
    class, and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning
    class or the evening class (catch-up classes for adults), the answer
    will not be the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the
    two classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and
    -1, depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the
    product of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me):
    Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by
    setting (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula
    Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form
    Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes:
    Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1,
    which gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the
    misunderstanding of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians
    become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    If we define complex multiplication in the way you suggest instead of
    the conventional way, that would mean that the operation of
    conjugation would no longer be a homomorphism with respect to the
    field of complex numbers under multiplication.

    So conj(z1*z2) would not be equal to conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    Thank you for your answer.

    But nevertheless, I continue to certify that there is an extremely fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we must pose i²=-1.

    But once we pose i=1, it is no longer possible to say i²=-1; and in the
    same way, when we pose i=-1, it is no longer possible to say 1²=-1.

    It is necessary, at this instant where we have defined i (whether it is
    1 or -1 but defined at this instant, it is necessary to set Z=z1*z2 such that:
    Z=(a+ib)(a'+ib')=aa'+bb'+i(ab'+a'b) to have the correct result,
    otherwise the real part becomes very incorrect.

    You tell me: yes, but it does not work with the conjugate.

    Of course it does.

    If it does not work, it is because you make a sign error, and the
    computer does the same because it is not formatted on the right concept giving the right real part.

    Mathematical proof that Z(conj)=z1(conj)*z2(conj)

    We set:
    z1=16+9i
    z2= 14+3i

    Z (equation correct)=aa'+bb'+i(ab'+a'b)

    Z=251+174i.

    Let z1(conj)=16-9i and z2(conj)=14-3i

    Z(conj)=aa'+bb'+i(ab'+a'b)
    Z(conj)=(16)(14)+(-3)(-9)+i[(16)(-3)+(14)(-9)]
    Z(conj)=251-174i

    R.H.

    I see I had an error in the desmos demonstration where it specified your alternative way of defining complex multiplication, and it seems that
    you're right with respect to conjugation remaining a homomorphism under
    your alternative definition.
    But taking the modulus would no longer be a homomorphism under your
    alternative definition, while it would be under the conventional definition.

    https://www.desmos.com/calculator/kijg1kvt75

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 15:28:03 2025
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:
    Le 19/01/2025 à 12:04, Moebius a écrit :
    Am 19.01.2025 um 08:51 schrieb Richard Hachel:

    But nevertheless, I continue to certify that there is an extremely
    fine mathematical error [...]

    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we [...]

    i is neither 1 nor -1.

    I consider (I could be wrong) that this is a case where we do not know
    what i is worth, and we hesitate between two values.

    No, we don't.

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
    i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    Simple as that.

    See: https://www.quora.com/Are-complex-numbers-the-same-as-ordered-pairs-of-real-numbers-or-is-there-more-to-them-than-that-Is-there-anything-that-we-can-do-with-complex-numbers-that-its-impossible-to-do-with-real-numbers

    and: https://www.math.uh.edu/~etgen/ComplexNos.pdf

    .
    .
    .

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From sobriquet@21:1/5 to All on Sun Jan 19 15:18:21 2025
    Op 19/01/2025 om 15:09 schreef sobriquet:
    Op 19/01/2025 om 08:51 schreef Richard Hachel:
    Le 19/01/2025 à 02:53, sobriquet a écrit :
    Op 18/01/2025 om 11:34 schreef Richard Hachel:
    Hello friends of mathematics.
    I was recently thinking, because of a poster named Python, about
    what complex numbers were, wondering if teaching them was so
    important and useful, especially in kindergarten where children are
    only learning to read.
    What is a complex number? Many have difficulty answering, especially
    girls, whose minds are often more practical than abstract.

    Let z=a+ib

    It is a number that has a real component and an imaginary component.

    I wonder if the terms "certain component" and "possible component"
    would not be as appropriate.

    What is i?

    It is an imaginary unit, such that i*i=-1.

    In our universe, this seems impossible, a square can never be negative. >>>>
    Except that we are in the imaginary.

    Let's assume that i is a number, or rather a unit, which is both its
    number and its opposite.

    Thus, if we set z=9i we see that z is both, as in this story of
    Schrödinger's cat, z=9 and z=-9

    I remind you that we are in the imaginary. So why not.

    Let's set z=16+9i

    It then comes that at the same time, z=25 and z=7.

    It is a strange universe, but which can be useful for writing things
    in different ways.

    Explanations: We ask Mrs. Martin how many students she has in her
    class, and she is very bored to answer because she does not know if
    Schrödinger's cat is dead.

    It has two classes, and depending on whether we imagine the morning
    class or the evening class (catch-up classes for adults), the answer
    will not be the same. There is no absolute answer. What is z?

    We can nevertheless give z a real part, which is the average of the
    two classes. a=16.

    And ib then becomes the fluctuation of the average.

    If we set i=1 then ib=+9; if we set i=-1 then ib=-9.

    "i" would therefore be this entity, this unit, equal to both 1 and
    -1, depending on how we look at it (Schrodinger's cat).

    But what happens if we square i?

    It is both 1 and -1?

    Can we write i²=(1)*(1)=1?

    No, because i would only be 1.

    Can we write i²=(-1)(-1)=1?

    No, because i is not only -1, it is both -1 and 1.

    We then have i²=(i)*(i)=(1)(-1)=(-1)(1)=-1.

    But here, we will notice something extraordinary, the additions and
    products of complex numbers can be determined.

    Z=z1+z2

    Z=(a+ib)+(a'+ib')

    and, Z=(a+a')+i(b+b')

    All this is very simple for the moment.

    But we are going to enter into a huge astonishment concerning the
    product of two complexes.

    How do mathematicians practice?
    Z=z1*z2

    so, so far it's correct:

    Z=(a+ib)(a'+ib')

    So, and it's still correct for Dr. Hachel (that's me):
    Z=aa'+i(ab'+a'b)+(ib)(ib')

    And there, for Dr. Hachel, mathematicians make a huge blunder by
    setting (ib)(ib')=i²bb'=-bb'

    Why?

    Because at this point in the calculation, we impose that i will
    indefinitely remain
    both positive and negative, and the correct formula
    Z=aa'+i(ab'+a'b)+(ib)(ib') will become incorrect written in the form
    Z=aa'+i(ab'+a'b)+(i²bb') and a sign error will appear.

    We must therefore write, for the product of two complexes:
    Z=aa'+bb'+i(ab'+a'b) and not aa'-bb'+i(ab'+a'b)

    The real part of the product being aa'+bb' and not aa'-bb'

    With a remaining imaginary part where i is equal to both -1 and 1,
    which gives two results each time for Z.

    It seems that this is an astonishing blunder, due to the
    misunderstanding of the handling of complex and imaginary numbers.

    On the other hand, by going through statistics, statistics confirms
    HAchel's ideas, and the results usually proposed by mathematicians
    become totally false.

    I wish you a good reflection on this.

    Have a good day.

    R.H.

    If we define complex multiplication in the way you suggest instead of
    the conventional way, that would mean that the operation of
    conjugation would no longer be a homomorphism with respect to the
    field of complex numbers under multiplication.

    So conj(z1*z2) would not be equal to conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    Thank you for your answer.

    But nevertheless, I continue to certify that there is an extremely
    fine mathematical error, at the moment when physicists pose
    i²=-1 to quickly simplify what seems a convenient operation.

    Because as long as we do not know what i is worth, which can be BOTH
    equal to 1 or -1 in this imaginary mathematics, we must pose i²=-1.

    But once we pose i=1, it is no longer possible to say i²=-1; and in
    the same way, when we pose i=-1, it is no longer possible to say 1²=-1.

    It is necessary, at this instant where we have defined i (whether it
    is 1 or -1 but defined at this instant, it is necessary to set Z=z1*z2
    such that:
    Z=(a+ib)(a'+ib')=aa'+bb'+i(ab'+a'b) to have the correct result,
    otherwise the real part becomes very incorrect.

    You tell me: yes, but it does not work with the conjugate.

    Of course it does.

    If it does not work, it is because you make a sign error, and the
    computer does the same because it is not formatted on the right
    concept giving the right real part.

    Mathematical proof that Z(conj)=z1(conj)*z2(conj)

    We set:
    z1=16+9i
    z2= 14+3i

    Z (equation correct)=aa'+bb'+i(ab'+a'b)

    Z=251+174i.

    Let z1(conj)=16-9i and z2(conj)=14-3i

    Z(conj)=aa'+bb'+i(ab'+a'b)
    Z(conj)=(16)(14)+(-3)(-9)+i[(16)(-3)+(14)(-9)]
    Z(conj)=251-174i

    R.H.

    I see I had an error in the desmos demonstration where it specified your alternative way of defining complex multiplication, and it seems that
    you're right with respect to conjugation remaining a homomorphism under
    your alternative definition.
    But taking the modulus would no longer be a homomorphism under your alternative definition, while it would be under the conventional
    definition.

    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration, so you can drag the blue and yellow
    point to pick any combination of two complex numbers and the resulting
    product of the two numbers will be indicated in cyan (the conventional definition) and green (your alternative definition). I think it's
    helpful to pick points within the unit circle, since that will result in
    a product that is also within the unit circle (or slightly outside of
    the unit circle in case of the alternative way to define a product).

    https://www.desmos.com/calculator/mptrtggp7x

    It's a desirable property of complex numbers that they multiply in a
    nice way in polar form, where the polar form of the product of two
    complex numbers will have a modulus that is the product of the modulus
    of the inputs and have an argument that is the sum of the arguments of
    the inputs.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Sun Jan 19 15:32:16 2025
    Le 19/01/2025 à 15:18, sobriquet a écrit :
    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration

    Basée sur une équation fausse.

    On tourne en rond.

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Sun Jan 19 15:30:14 2025
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Then
    i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    i=1=-1

    C'est complétement différent.



    Simple as that.

    Vous dites que i n'est ni 1, ni -1.

    Je dis qu'il est les deux.

    C'est complétement différent.

    Et je gagne, parce que si je vous dis, mais alors, pour vous, il est
    quoi? Comment définissez-vous cette "autre chose"?

    Vous ne savez pas répondre de façon positive.

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Python@21:1/5 to All on Sun Jan 19 15:34:22 2025
    Le 19/01/2025 à 16:30, Richard Hachel a écrit :
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Then
    i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    i=1=-1

    C'est complétement différent.



    Simple as that.

    Vous dites que i n'est ni 1, ni -1.

    Je dis qu'il est les deux.

    C'est complétement différent.

    So you're talk talking about Complex Numbers.

    Et je gagne, parce que si je vous dis, mais alors, pour vous, il est quoi? Comment définissez-vous cette "autre chose"?

    Vous ne savez pas répondre de façon positive.

    Of course we can. There are even several ways to define "positively" what
    i is, what C is.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Python@21:1/5 to All on Sun Jan 19 15:35:06 2025
    Le 19/01/2025 à 16:30, Richard Hachel a écrit :
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Then
    i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    i=1=-1

    C'est complétement différent.



    Simple as that.

    Vous dites que i n'est ni 1, ni -1.

    Je dis qu'il est les deux.

    C'est complétement différent.

    So you're NOT talking about Complex Numbers.

    Et je gagne, parce que si je vous dis, mais alors, pour vous, il est quoi? Comment définissez-vous cette "autre chose"?

    Vous ne savez pas répondre de façon positive.

    Of course we can. There are even several ways to define "positively" what
    i is, what C is.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to hence we may on Sun Jan 19 16:50:13 2025
    Am 19.01.2025 um 16:39 schrieb Moebius:
    Am 19.01.2025 um 16:30 schrieb Richard Hachel:
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    Yes.

    Hint: Then (in this context) i * i = (0, 1) * (0, 1) = (-1, 0), the
    latter is "identified" with -1, hence we may write:

    i^2 = -1 .

    That's exactly what we want.

    i = 1 = -1

    Hear, hear, hence 1 = -1 now?

    Fuck off, idiot!

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 16:43:55 2025
    Am 19.01.2025 um 16:34 schrieb Python:
    Le 19/01/2025 à 16:30, Richard Hachel  a écrit :
    Le 19/01/2025 à 15:28, Moebius a écrit :

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then [usually]:

             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

     No.

    Yes.

     i = 1 = -1

    Nonsens. Hint: 1 =/= -1.

     C'est complétement différent.


    Simple as that.

     Vous dites que i n'est ni 1, ni -1.

     Je dis qu'il est les deux.

     C'est complétement différent.

    So you're talk talking about Complex Numbers.

    "So you're NOT talking about Complex Numbers." - right?

    Et je gagne, parce que si je vous dis, mais alors, pour vous, il est
    quoi? Comment définissez-vous cette "autre chose"?
    Vous ne savez pas répondre de façon positive.

    Of course we can. There are even several ways to define "positively"
    what i is, what C is.

    Indeed.

    .
    .
    .

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 17:04:38 2025
    Am 19.01.2025 um 16:50 schrieb Moebius:
    Am 19.01.2025 um 16:39 schrieb Moebius:
    Am 19.01.2025 um 16:30 schrieb Richard Hachel:
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    Yes.

    Hint: Then (in this context) i * i = (0, 1) * (0, 1) = (-1, 0), the
    latter is "identified" with -1, hence we may write:

                     i^2 = -1 .

    That's exactly what we want.

    Hint: No "extremely fine mathematical error" at all.

    On the other hand, this one is an "extremely severe mathematical error":

    i = 1 = -1

    Hear, hear, hence 1 = -1 now?

    Fuck off, idiot!


    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 16:39:51 2025
    Am 19.01.2025 um 16:30 schrieb Richard Hachel:
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    Yes.

    i = 1 = -1

    Hear, hear, hence 1 = -1 now?

    Fuck off, idiot!

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Python@21:1/5 to All on Sun Jan 19 16:21:32 2025
    Le 19/01/2025 à 17:04, Moebius a écrit :
    Am 19.01.2025 um 16:50 schrieb Moebius:
    Am 19.01.2025 um 16:39 schrieb Moebius:
    Am 19.01.2025 um 16:30 schrieb Richard Hachel:
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    Yes.

    Hint: Then (in this context) i * i = (0, 1) * (0, 1) = (-1, 0), the
    latter is "identified" with -1, hence we may write:

                     i^2 = -1 .

    That's exactly what we want.

    Hint: No "extremely fine mathematical error" at all.

    On the other hand, this one is an "extremely severe mathematical error":

    Richard "Hachel" Lengrand suffers of a lot of mental diseases. One of them
    is pathological hubris. When he fails to understand something (and he
    failed to understand complex numbers when in high schools, then he
    studied... medicine) instead of thinking and studying the subject he systematically decides that everyone is wrong and he pretend to reinvent
    the subjet.

    He's doing this for Special Relativity for decades and ended up with an atrocious bunch of nonsense and contradiction.

    He cannot realize that there cannot be an "error" in a definition, such as
    the ones for complex numbers.

    Either it is consistent, compatible with general algebraic structures and useful or not.

    Complex numbers are consistent, they form a Field extending R, allowing to factorize all polynomials better than in R[X]. They allow to utterly
    simplify a lot of geometric problems and deduce trigonometric identity.

    They are not the only interesting structures on R^2 btw, dual numbers
    defined by a+b*epsilon where epsilon^2 = 0 (more rigorously this is the
    ring R[X]/X^2, while epsilon is the equivalence class of the polynomial X, quite a similar approach to the algebraic construction of C as
    R[X]/(X^1+1))

    Dual numbers provide a very elegant introduction of calculus without
    having to deal with limites (at least for polynomials).

    Hachel/Lengrand's "ideas" may have had some sense, but they are 100%
    unrelated to complex numbers. Moreover the idea of something having two distinct values -1 and 1 is, of course, totally absurd and contradictory.
    Given his deranged mental states Richard does not bother.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 18:25:52 2025
    Am 19.01.2025 um 18:16 schrieb guido wugi:
    Op 19/01/2025 om 16:32 schreef Richard Hachel:
    Le 19/01/2025 à 15:18, sobriquet a écrit :
    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration

    Basée sur une équation fausse.

    On tourne en rond.

    Not "on", but "only" you ;)

    The definition of "i" is simple: it's a solution of the equation i^2 = -1.

    If there is such a solution. :-P

    Actually, there are 2 such solutions in C. So which one is i?

    Hence I'd perefer tp claim that i is a number such that i^2 = -1. (-i is another one.)

    So it's clear from the start that it's not a member of the real number line [...]

    Right.

    It's simply some "other number" outside the real number line, one
    creating its own number line.

    I guess you mean ix (with x e IR). Right.

    What's there more to brood on?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From guido wugi@21:1/5 to All on Sun Jan 19 18:16:10 2025
    Op 19/01/2025 om 16:32 schreef Richard Hachel:
    Le 19/01/2025 à 15:18, sobriquet a écrit :
    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration

    Basée sur une équation fausse.

    On tourne en rond.

    Not "on", but "only" you ;)

    The definition of "i" is simple: it's a solution of the equation i^2=-1.

    So it's clear from the start that it's not a member of the real number
    line, and thus
    neither a doubting case, or Schrödinger cat limbo state case, between
    [+1 and -1],
    neither a case where it should be alternatively +1 and -1, to have
    i*i=-1 work...

    It's simply some "other number" outside the real number line, one
    creating its own number line.
    What's there more to brood on?

    --
    guido wugi

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From sobriquet@21:1/5 to All on Sun Jan 19 20:02:26 2025
    Op 19/01/2025 om 16:32 schreef Richard Hachel:
    Le 19/01/2025 à 15:18, sobriquet a écrit :
    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration

    Basée sur une équation fausse.

    On tourne en rond.

    R.H.

    The latest desmos links should have the correct equation. If not, could
    you please be specific and point out which equation in the list of
    expressions on the left side is incorrect?.

    One striking feature of conventional products is that the product of
    complex numbers on the unit circle ends up on the unit circle and your alternative way to define multiplication doesn't have that feature:

    https://www.desmos.com/calculator/g4nxgeszqc

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Sun Jan 19 19:17:09 2025
    Am 19.01.2025 um 18:16 schrieb guido wugi:
    Op 19/01/2025 om 16:32 schreef Richard Hachel:
    Le 19/01/2025 à 15:18, sobriquet a écrit :
    https://www.desmos.com/calculator/kijg1kvt75

    It's an interactive demonstration

    Basée sur une équation fausse.

    On tourne en rond.

    Not "on", but "only" you ;)

    The definition of "i" is simple: it's a solution of the equation [x^2 = -1].

    If there is such a solution. :-P

    Actually, there are 2 such solutions in C. So which one is i?

    Hence I'd perefer tp claim that i is a number such that i^2 = -1. (-i is another one.)

    So it's clear from the start that it's not a member of the real number line [...]

    Right.

    It's simply some "other number" outside the real number line, one
    creating its own number line.

    I guess you mean ix (with x e IR). Right.

    What's there more to brood on?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Moebius@21:1/5 to All on Mon Jan 20 00:12:34 2025
    Am 19.01.2025 um 17:21 schrieb Python:

    [Mr. NN] suffers of a lot of mental diseases. One of them is pathological hubris. When he fails to understand something [...] instead of thinking and studying the subject he systematically decides that everyone is wrong and he pretend to [understand]
    the subject [better than everyone else].

    Talking about Mückenheim? :-)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jim Burns@21:1/5 to Richard Hachel on Sun Jan 19 18:40:51 2025
    cOn 1/19/2025 2:41 AM, Richard Hachel wrote:
    Le 19/01/2025 à 02:53, sobriquet a écrit :
    Op 18/01/2025 om 11:34 schreef Richard Hachel:

    I was recently thinking,
    because of a poster named Python,
    about what complex numbers were,
    wondering if teaching them was so important and useful,
    especially in kindergarten
    where children are only learning to read.
    What is a complex number?

    Let z=a+ib
    It is a number that has
    a real component and an imaginary component.

    I wonder if the terms
    "certain component" and "possible component"
    would not be as appropriate.

    The terms 'real' and 'imaginary' are hand.me.downs
    from the fabled.past of mathematics.
    They might not always be a perfect fit.

    If I decided to update our vocabulary,
    for the sake of the children, perhaps,
    I would select terms suggesting two directions.
    For example, 'east' and 'north'.

    What is i?
    It is an imaginary unit, such that i*i=-1.

    It is a unit north.
    Multiplication by i is a left turn.
    Multiplication by i twice reverses direction.

    Let's assume that i is a number, or rather a unit,
    which is both its number and its opposite.

    Let's not assume that a unit north is
    both a unit east and a unit west.

    Thus,
    if we set z=9i
    we see that z is both,
    as in this story of Schrödinger's cat,
    z=9 and z=-9

    I remind you that we are in the imaginary.
    So why not.

    Because z = z but 9 ≠ -9

    ⎛ Schrödinger's cat asks questions other than
    ⎜ how far north.south.east.west.

    ⎜ Experiments and Bell's theorem seem to say that,
    ⎜ before we look,
    ⎜ the cat doesn't have
    ⎜ either a past in which it died
    ⎜ or a past in which it survived.

    ⎜ But then we look, and _when we look_
    ⎜ we see a cat with one of those pasts.

    ⎜⎛
    ⎜⎜ The Moving Finger writes; and, having writ,
    ⎜⎜ Moves on: nor all thy Piety nor Wit
    ⎜⎜ Shall lure it back to cancel half a Line,
    ⎜⎜ Nor all thy Tears wash out a Word of it.
    ⎜⎝
    ⎜ -- Omar Khayyam, trans. Edward FitzGerald

    ⎜ What if, for just a moment,
    ⎜ we can hold the door to the cat shut, and,
    ⎜ for just that moment, the finger pauses,
    ⎜ and history isn't written -- yet.

    ⎜ But always our hand slips, the door opens,
    ⎜ the finger writes and moves on.
    ⎜ Holding that door shut
    ⎝ is very challenging, technically.

    If we define complex multiplication
    in the way you suggest
    instead of the conventional way,
    that would mean that
    the operation of conjugation would no longer be
    a homomorphism with respect to
    the field of complex numbers under multiplication.

    Conventionally,
    when you stand on your head (conjugation),
    all this makes (conjugated) sense.

    So conj(z1*z2) would not be equal to
    conj(z1)*conj(z2).

    https://www.desmos.com/calculator/kqzgbliix1

    Because as long as we do not know what i is worth,
    which can be BOTH equal to 1 or -1
    in this imaginary mathematics, we must pose i²=-1.

    For ⅈ=1 or ⅈ=-1, ⅈ²=1 or ⅈ²=1

    You tell me:
    yes, but it does not work with the conjugate.

    I vaguely recall, from a course in complex analysis
    I took approximately When Dinosaurs Ruled The Earth,
    that, by requiring the complex field axioms
    to be satisfied, one can generate ⅈ²=-1 algebraically.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Mon Jan 20 10:11:32 2025
    Le 19/01/2025 à 16:39, Moebius a écrit :
    Am 19.01.2025 um 16:30 schrieb Richard Hachel:
    Le 19/01/2025 à 15:28, Moebius a écrit :
    Am 19.01.2025 um 12:37 schrieb Richard Hachel:

    Complex numbers can be defined as (ordered) pairs of real numbers.

    Then
             i := (0, 1) .

    Hence i =/= 1 and i =/= -1.

    No.

    Yes.

    i = 1 = -1

    Hear, hear, hence 1 = -1 now?

    Fuck off, idiot!

    Ce n'est pas ce que je dis, O saint crétin.

    J'ai dit que dans le monde des nombres complexes (qui ne sont pas si
    complexes que ça si l'on comprend ce que l'on est en train de faire) nous parlions de nombres i et z, imaginaires.

    i, selon l'immense Hachel, triple pris Nobel dans vos gueules quand même,
    est l'unité imaginaire, qui est, à la fois, égal à -1 et 1.

    z est un nombre imaginaire qui contient une partie ferme, compacte,
    réelle, et une partie bicéphale imagianaire qui le rend, lui aussi,
    double. Ainsi, par exemple, z vaut 25 et 7 tout à la fois si l'on donne
    à z l'identité suivante : z=16+9i.

    Tu comprends, O crétin?

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Mon Jan 20 10:58:16 2025
    Le 20/01/2025 à 00:40, Jim Burns a écrit :
    cOn 1/19/2025 2:41 AM, Richard Hachel wrote:
    Le 19/01/2025 à 02:53, sobriquet a écrit :

    For ⅈ=1 or ⅈ=-1, ⅈ²=1 or ⅈ²=1

    I answered this in the previous post.

    I said that mathematicians confuse, when squaring i, the following two
    objects.

    i²=|i²|
    and i²= |i|²

    I repeat, when we do not know z, which can have two values
    ​​simultaneously (as in my example of the Plougastel high school),
    we must give i an imaginary value, and i is neither 1 nor -1, but both at
    the same time.

    And its square becomes i²=(-1)(1)=-1

    But as soon as we know it (we can photograph it when it is -1 or when it
    is 1), we must no longer consider it as a duplicate.

    If it is -1, we must follow the idea through to the end: (a+ib)(a'+ib')=aa'-(ab'+a'b)+bb'
    Same for i=1
    (a+ib)(a'+ib')=aa'+(ab'+a'b)+bb'

    We then realize that for the real part, we always have,
    A=aa'+bb' whatever the value given to i.

    On the other hand, and here, let's reintroduce i to make only one of the
    two equations:

    Z=aa'+i(ab'+a'b)+bb'

    where i can resume its bipolarity without any problem, while aa'+bb' is a correct real part for the equation.

    Do you understand these things?

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Mon Jan 20 10:42:31 2025
    Le 19/01/2025 à 20:02, sobriquet a écrit :

    The latest desmos links should have the correct equation. If not, could
    you please be specific and point out which equation in the list of expressions on the left side is incorrect?.

    One striking feature of conventional products is that the product of
    complex numbers on the unit circle ends up on the unit circle and your alternative way to define multiplication doesn't have that feature:

    I gave yesterday the formula for the addition of complex numbers as I
    gave, a long time ago already, the correct formula for the general
    addition of relativistic speeds.
    I put it here again as an example.
    Addition formula:
    (a+ib)+(a'-ib')=(a+a')+i(b+b')
    Multiplication formula:
    (a+ib)(a'+ib')=aa'+(ib')a+(ib)a'+(ib)(ib')

    Here, during the simplification, we must be careful not to make a colossal blunder. It is the product (ib)(ib') that will produce this blunder,
    because the mathematician will not take care that (ib)(ib') is NOT
    |i²|bb BUT |i|²bb'.

    Here Hachel (it's me) then poses:
    (a+ib)(a'+ib')=aa'+i(ab'+a'b)+bb'
    and no longer:
    (a+ib)(a'+ib')=aa'+i(ab'+a'b)-bb' which is a false result in its real part aa'+bb'.

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Mon Jan 20 10:29:41 2025
    Le 19/01/2025 à 18:16, guido wugi a écrit :

    Not "on", but "only" you ;)

    The definition of "i" is simple: it's a solution of the equation i^2=-1.

    So it's clear from the start that it's not a member of the real number
    line, and thus
    neither a doubting case, or Schrödinger cat limbo state case, between
    [+1 and -1],
    neither a case where it should be alternatively +1 and -1, to have
    i*i=-1 work...

    It's simply some "other number" outside the real number line, one
    creating its own number line.
    What's there more to brood on?

    Nothing prevents me from thinking that i is a special unit, existing in an imaginary world, and which is neither 1 nor -1.

    If it were -1 or 1, its square would be 1.

    This is also what it becomes once the equation is posed, when it is
    presented under the visible face of the moon, we immediately have i²=1 whatever the observed value (-1 or 1).

    As long as it is not observed, that we do not know what it is, we can only imagine two solutions, and in the imagination, it is worth both 1 and -1.

    At this precise moment of imagination, i having both values, we have (i)(i)=(-1)(1)=-1=i².

    The immense error of mathematicians is then to consider that i remains
    forever unknown. This is false. We can then give TWO solutions to z (which
    is an imaginary double number) z=a+ib

    But if we give the first solution, with i=-1, we get
    as a product (a+ib)(a'+ib')=aa+bb+i(ab'+a'b). And exactly the same thing
    for i=1. Because each time, i being known, we can simplify like this.
    We then just have to reintroduce the uncertainty, in the equation, which
    now contains only one ito have the two solutions.

    But in each solution, the real part remains the same, and it is aa+bb',
    and certainly not aa'-bb".

    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Mon Jan 20 14:08:35 2025
    Le 19/01/2025 à 17:21, Python a écrit :
    Le 19/01/2025 à 17:04, Moebius a écrit :

    the idea of something having two distinct values -1 and 1 is, of course, totally
    absurd and contradictory. Given his deranged mental states Richard does not bother.

    Ce n'est pas plus absurde que de dire que le chat de Schödinger est à
    la fois mort et vivant.

    De plus, nous sommes en univers imaginaire, c'est à dire "au-delà du
    réel".

    Je trouve tes griefs un peu déplacés quand ils ne sont pas carrément mensongers ou diffamatoires.

    Je rappelle le problème du collège de Plougastel?

    Combien y a-t-il d'élèves dans la classe de madame Martin?

    Madame Martin ne peut pas répondre, car cela dépend de l'heure de la
    visite de l'inspecteur d'académie.

    La réponse proposée est donc z, qui peut prendre deux valeurs, selon
    qu'on imagine que l'inspecteur vient
    le matin, ou à l'heure du cours de rattrapage pour adulte, le soir,
    après le travail.

    z1=16+9i

    Idem pour Mlle Watson, élémentaire, mon cher Python, z2=14+3i

    Reste la notion d'addition, qui est celle de monsieur le proviseur, qui
    lui supervise les quatre classes.

    Combien a-t-il d'élèves?

    Z=z1+z2

    Z=(a+a')+i(b+b')

    Passons au produit de deux complexes (en utilisant la bonne formule).

    On imagine qu'on va envoyer, si l'inspecteur d'académie se pointe, sans
    qu'on sache le jour, ni l'heure (Jésus-Christ copyrights) un couple
    formé d'un garçon de madame Martin et d'une fille de Melle Watson.

    Z=z1*z2

    Docteur Hachel, immense génie dans ce monde de crétins dit:
    Z=(a+ib)*(a'+ib') et pose quelque chose d'hallucinant devant le monde
    entier médusé:
    Z=aa'+bb'+i(ab'+a'b) en affirmant qu'il faut poser ici i²=1 et non
    i²=-1 car i qu'il soit identifié
    comme i=1 ou i=-1 ne pourra plus avoir qu'un carré positif.

    Allons plus loin.

    Le produit de deux complexes étant connus, on fait l'opération inverse.

    Si z1*z2=Z on doit forcément avoir Z/z1=z2 et Z/z2=z1

    Comment calcule-t-on z2=Z/z1 ou z1=Z/z2 ?

    Posons par exemple :

    Z=A+iB

    z1=a+ib

    z2=Z/z1

    z2= ?



    R.H.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Python@21:1/5 to All on Mon Jan 20 17:26:12 2025
    Le 20/01/2025 à 15:08, Richard Hachel a écrit :
    Le 19/01/2025 à 17:21, Python a écrit :
    Le 19/01/2025 à 17:04, Moebius a écrit :

    the idea of something having two distinct values -1 and 1 is, of course, totally
    absurd and contradictory. Given his deranged mental states Richard does not bother.

    Ce n'est pas plus absurde que de dire que le chat de Schödinger est à la fois
    mort et vivant.

    De plus, nous sommes en univers imaginaire, c'est à dire "au-delà du réel".

    Je trouve tes griefs un peu déplacés quand ils ne sont pas carrément mensongers ou diffamatoires.

    Je rappelle le problème du collège de Plougastel?

    Combien y a-t-il d'élèves dans la classe de madame Martin?

    Madame Martin ne peut pas répondre, car cela dépend de l'heure de la visite
    de l'inspecteur d'académie.

    La réponse proposée est donc z, qui peut prendre deux valeurs, selon qu'on imagine que l'inspecteur vient
    le matin, ou à l'heure du cours de rattrapage pour adulte, le soir, après le
    travail.

    z1=16+9i

    Idem pour Mlle Watson, élémentaire, mon cher Python, z2=14+3i

    Reste la notion d'addition, qui est celle de monsieur le proviseur, qui lui supervise les quatre classes.

    Combien a-t-il d'élèves?

    Z=z1+z2

    Z=(a+a')+i(b+b')

    Passons au produit de deux complexes (en utilisant la bonne formule).

    On imagine qu'on va envoyer, si l'inspecteur d'académie se pointe, sans qu'on
    sache le jour, ni l'heure (Jésus-Christ copyrights) un couple formé d'un garçon
    de madame Martin et d'une fille de Melle Watson.

    Z=z1*z2

    Docteur Hachel, immense génie dans ce monde de crétins dit:
    Z=(a+ib)*(a'+ib') et pose quelque chose d'hallucinant devant le monde entier médusé:
    Z=aa'+bb'+i(ab'+a'b) en affirmant qu'il faut poser ici i²=1 et non i²=-1 car
    i qu'il soit identifié
    comme i=1 ou i=-1 ne pourra plus avoir qu'un carré positif.

    Allons plus loin.

    Le produit de deux complexes étant connus, on fait l'opération inverse.

    Si z1*z2=Z on doit forcément avoir Z/z1=z2 et Z/z2=z1

    Comment calcule-t-on z2=Z/z1 ou z1=Z/z2 ?

    Posons par exemple :

    Z=A+iB

    z1=a+ib

    z2=Z/z1

    z2= ?



    R.H.

    Abruti ! Tu es pathétiquement complètement à côté de la plaque, pour
    ne pas changer. Si tu réponds en français fais le sur fr.sci.maths (et
    non pas en cuistre sur sci.*) où je te répondrai volontiers en
    français.

    Idiot! You are pathetically off track, as usual. If you answer in French,
    show some respects to people on Usenet do so on fr.sci.maths not here. I
    could answer you there.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jim Burns@21:1/5 to Richard Hachel on Thu Jan 30 16:55:27 2025
    On 1/18/2025 5:34 AM, Richard Hachel wrote:

    I was recently thinking,
    because of a poster named Python,
    about what complex numbers were,
    wondering if teaching them was so important and useful,
    especially in kindergarten
    where children are only learning to read.
    What is a complex number?

    What is i?

    It is an imaginary unit, such that i*i=-1.

    ⟨ℝ,+,⋅⟩ is a field, which means:
    '+','⋅': ℝ×ℝ → ℝ
    are associative and commutative, and
    have identities 0,1 and inverses -x,x⁻¹,
    except there's no 0⁻¹,
    and '⋅' distributes over '+'.

    ⟨ℝ²,⨢,∘⟩ is a field, which means:
    '⨢','∘': ℝ²×ℝ² → ℝ²
    are associative and commutative, and
    have identities 𝟎,𝒆₁ = [1 0] and inverses -𝐱,𝐱⁻¹,
    except there's no 𝟎⁻¹,
    and '∘' distributes over '⨢'.

    ⟨ℝ²,⨢,∘⟩ is defined to be
    an extension of ⟨ℝ,+,⋅⟩, which means:
    '⨢' and '∘' agree with '+' and '⋅' on ℝ×{0}
    and, on the whole ℝ², is a field.

    '∘' is bilinear, and
    𝒆₁ is left.unit and right.unit.
    ⎛ (c⋅𝐫)∘𝐬 = c⋅(𝐫∘𝐬)
    ⎜ (𝐫⨢𝐭)∘𝐬 = 𝐫∘𝐬 ⨢ 𝐭∘𝐬
    ⎜ 𝐫∘(c⋅𝐬) = c⋅(𝐫∘𝐬)
    ⎜ 𝐫∘(𝐬⨢𝐭) = 𝐫∘𝐬 ⨢ 𝐫∘𝐭
    ⎜ 𝒆₁∘𝐬 = 𝐬
    ⎝ 𝐫∘𝒆₁ = 𝐫

    That's enough information to determine a lot of,
    but not all of the definition of '∘'.

    Let 𝒆₂ = [0 1]
    and 𝒆₂∘𝒆₂ = [-μ₁ -μ₂]. (a𝒆₁⨢b𝒆₂)∘(c𝒆₁⨢d𝒆₂) = (ac-μ₁bd)𝒆₁⨢(ad+bc-μ₂bd)𝒆₂

    μ₁ > μ₂²/4
    iff
    a point 𝒊 exists such that 𝒊∘𝒊 = -𝒆₁
    𝒊 = ±[μ₂/2 1]/(μ₁-μ₂²/4)¹ᐟ²
    and
    (a𝒆₁⨢b𝒊)∘(c𝒆₁⨢d𝒊) = (ac-bd)𝒆₁⨢(ad+bc)𝒊
    and
    the constants μ₁,μ₂ disappear from view,
    disappear into 𝒊, in effect,
    and
    for each 𝐫 ≠ 𝟎, 𝐫⁻¹ exists, 𝐫∘𝐫⁻¹ = 𝒆₁
    and
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    There are different values possible for 𝒆₂∘𝒆₂ = [-μ₁ -μ₂], but, as long as μ₁ > μ₂²/4,
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    For two plane.multiplications ∘′ and ∘″
    we can map 𝒊′ ⟷ 𝒊″
    and then
    (a𝒆₁⨢b𝒊′)∘′(c𝒆₁⨢d𝒊′) = (ac-bd)𝒆₁⨢(ad+bc)𝒊′
    (a𝒆₁⨢b𝒊″)∘″(c𝒆₁⨢d𝒊″) = (ac-bd)𝒆₁⨢(ad+bc)𝒊″

    And the two ℝ.extending plane.multiplications
    are isomorphic.
    Therefore, there is
    only one extension of ℝ to ℝ², up to isomorphism,
    and, for that extension, 𝒊² = -1

    ⎛ What I got wrong initially was that 𝒊 ≠ 𝒆₂,
    ⎜ at least, not necessarily equal.
    ⎜ That it's not doesn't matter, though.
    ⎜ All the different '∘' with their different 𝒊
    ⎝ map to each other very neatly.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Hachel@21:1/5 to All on Thu Jan 30 22:39:09 2025
    Le 30/01/2025 à 22:55, Jim Burns a écrit :
    On 1/18/2025 5:34 AM, Richard Hachel wrote:

    I was recently thinking,
    because of a poster named Python,
    about what complex numbers were,
    wondering if teaching them was so important and useful,
    especially in kindergarten
    where children are only learning to read.
    What is a complex number?

    What is i?

    It is an imaginary unit, such that i*i=-1.

    ⟨ℝ,+,⋅⟩ is a field, which means:
    '+','⋅': ℝ×ℝ → ℝ
    are associative and commutative, and
    have identities 0,1 and inverses -x,x⁻¹,
    except there's no 0⁻¹,
    and '⋅' distributes over '+'.

    ⟨ℝ²,⨢,∘⟩ is a field, which means:
    '⨢','∘': ℝ²×ℝ² → ℝ²
    are associative and commutative, and
    have identities 𝟎,𝒆₁ = [1 0] and inverses -𝐱,𝐱⁻¹,
    except there's no 𝟎⁻¹,
    and '∘' distributes over '⨢'.

    ⟨ℝ²,⨢,∘⟩ is defined to be
    an extension of ⟨ℝ,+,⋅⟩, which means:
    '⨢' and '∘' agree with '+' and '⋅' on ℝ×{0}
    and, on the whole ℝ², is a field.

    '∘' is bilinear, and
    𝒆₁ is left.unit and right.unit.
    ⎛ (c⋅𝐫)∘𝐬 = c⋅(𝐫∘𝐬)
    ⎜ (𝐫⨢𝐭)∘𝐬 = 𝐫∘𝐬 ⨢ 𝐭∘𝐬
    ⎜ 𝐫∘(c⋅𝐬) = c⋅(𝐫∘𝐬)
    ⎜ 𝐫∘(𝐬⨢𝐭) = 𝐫∘𝐬 ⨢ 𝐫∘𝐭
    ⎜ 𝒆₁∘𝐬 = 𝐬
    ⎝ 𝐫∘𝒆₁ = 𝐫

    That's enough information to determine a lot of,
    but not all of the definition of '∘'.

    Let 𝒆₂ = [0 1]
    and 𝒆₂∘𝒆₂ = [-μ₁ -μ₂]. (a𝒆₁⨢b𝒆₂)∘(c𝒆₁⨢d𝒆₂) = (ac-μ₁bd)𝒆₁⨢(ad+bc-μ₂bd)𝒆₂

    μ₁ > μ₂²/4
    iff
    a point 𝒊 exists such that 𝒊∘𝒊 = -𝒆₁
    𝒊 = ±[μ₂/2 1]/(μ₁-μ₂²/4)¹ᐟ²
    and
    (a𝒆₁⨢b𝒊)∘(c𝒆₁⨢d𝒊) = (ac-bd)𝒆₁⨢(ad+bc)𝒊
    and
    the constants μ₁,μ₂ disappear from view,
    disappear into 𝒊, in effect,
    and
    for each 𝐫 ≠ 𝟎, 𝐫⁻¹ exists, 𝐫∘𝐫⁻¹ = 𝒆₁
    and
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    There are different values possible for 𝒆₂∘𝒆₂ = [-μ₁ -μ₂], but, as long as μ₁ > μ₂²/4,
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    For two plane.multiplications ∘′ and ∘″
    we can map 𝒊′ ⟷ 𝒊″
    and then
    (a𝒆₁⨢b𝒊′)∘′(c𝒆₁⨢d𝒊′) = (ac-bd)𝒆₁⨢(ad+bc)𝒊′ (a𝒆₁⨢b𝒊″)∘″(c𝒆₁⨢d𝒊″) = (ac-bd)𝒆₁⨢(ad+bc)𝒊″

    And the two ℝ.extending plane.multiplications
    are isomorphic.
    Therefore, there is
    only one extension of ℝ to ℝ², up to isomorphism,
    and, for that extension, 𝒊² = -1

    ⎛ What I got wrong initially was that 𝒊 ≠ 𝒆₂,
    ⎜ at least, not necessarily equal.
    ⎜ That it's not doesn't matter, though.
    ⎜ All the different '∘' with their different 𝒊
    ⎝ map to each other very neatly.

    Thank you for all these details.

    R.H.

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  • From guido wugi@21:1/5 to All on Fri Jan 31 12:31:03 2025
    Op 30/01/2025 om 22:55 schreef Jim Burns:
    On 1/18/2025 5:34 AM, Richard Hachel wrote:

    I was recently thinking,
    because of a poster named Python,
    about what complex numbers were,
    wondering if teaching them was so important and useful,
    especially in kindergarten
    where children are only learning to read.
    What is a complex number?

    What is i?

    It is an imaginary unit, such that i*i=-1.

    ⟨ℝ,+,⋅⟩ is a field, which means:
    '+','⋅': ℝ×ℝ → ℝ
    are associative and commutative, and
    have identities 0,1 and inverses -x,x⁻¹,
    except there's no 0⁻¹,
    and '⋅' distributes over '+'.

    ⟨ℝ²,⨢,∘⟩ is a field, which means:
    '⨢','∘': ℝ²×ℝ² → ℝ²
    are associative and commutative, and
    have identities 𝟎,𝒆₁ = [1 0] and inverses -𝐱,𝐱⁻¹,
    except there's no 𝟎⁻¹,
    and '∘' distributes over '⨢'.

    ⟨ℝ²,⨢,∘⟩ is defined to be
    an extension of ⟨ℝ,+,⋅⟩, which means:
    '⨢' and '∘' agree with '+' and '⋅' on ℝ×{0}
    and, on the whole ℝ², is a field.

    '∘' is bilinear, and
    𝒆₁ is left.unit and right.unit.
    ⎛ (c⋅𝐫)∘𝐬 = c⋅(𝐫∘𝐬)
    ⎜ (𝐫⨢𝐭)∘𝐬 = 𝐫∘𝐬 ⨢ 𝐭∘𝐬
    ⎜ 𝐫∘(c⋅𝐬) = c⋅(𝐫∘𝐬)
    ⎜ 𝐫∘(𝐬⨢𝐭) = 𝐫∘𝐬 ⨢ 𝐫∘𝐭
    ⎜ 𝒆₁∘𝐬 = 𝐬
    ⎝ 𝐫∘𝒆₁ = 𝐫

    That's enough information to determine a lot of,
    but not all of the definition of '∘'.

    Let 𝒆₂ = [0 1]
    and 𝒆₂∘𝒆₂ = [-μ₁ -μ₂]. (a𝒆₁⨢b𝒆₂)∘(c𝒆₁⨢d𝒆₂) = (ac-μ₁bd)𝒆₁⨢(ad+bc-μ₂bd)𝒆₂

    μ₁ > μ₂²/4
     iff
    a point 𝒊 exists such that 𝒊∘𝒊 = -𝒆₁
    𝒊 = ±[μ₂/2 1]/(μ₁-μ₂²/4)¹ᐟ²
    and
    (a𝒆₁⨢b𝒊)∘(c𝒆₁⨢d𝒊) = (ac-bd)𝒆₁⨢(ad+bc)𝒊
    and
    the constants μ₁,μ₂ disappear from view,
    disappear into 𝒊, in effect,
    and
    for each 𝐫 ≠ 𝟎, 𝐫⁻¹ exists, 𝐫∘𝐫⁻¹ = 𝒆₁
    and
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    There are different values possible for 𝒆₂∘𝒆₂ = [-μ₁ -μ₂], but, as long as μ₁ > μ₂²/4,
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    For two plane.multiplications ∘′ and ∘″
    we can map 𝒊′ ⟷ 𝒊″
    and then
    (a𝒆₁⨢b𝒊′)∘′(c𝒆₁⨢d𝒊′) = (ac-bd)𝒆₁⨢(ad+bc)𝒊′
    (a𝒆₁⨢b𝒊″)∘″(c𝒆₁⨢d𝒊″) = (ac-bd)𝒆₁⨢(ad+bc)𝒊″

    And the two ℝ.extending plane.multiplications
    are isomorphic.
    Therefore, there is
    only one extension of ℝ to ℝ², up to isomorphism,
    and, for that extension, 𝒊² = -1

    ⎛ What I got wrong initially was that 𝒊 ≠ 𝒆₂,
    ⎜ at least, not necessarily equal.
    ⎜ That it's not doesn't matter, though.
    ⎜ All the different '∘' with their different 𝒊
    ⎝ map to each other very neatly.

    Not sure I "got" it all. I once did, I guess, a similar thinkthing about
    not necessarily fields, but multidimensional numbers alright, as
    n-vectors and as "autovariant" nxn matrix families: https://www.wugi.be/hypereal.htm

    --
    guido wugi

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  • From Jim Burns@21:1/5 to guido wugi on Fri Jan 31 11:07:35 2025
    On 1/31/2025 6:31 AM, guido wugi wrote:
    Op 30/01/2025 om 22:55 schreef Jim Burns:

    There are different values possible for 𝒆₂∘𝒆₂ = [-μ₁ -μ₂], >> but, as long as μ₁ > μ₂²/4,
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    For two plane.multiplications ∘′ and ∘″
    we can map 𝒊′ ⟷ 𝒊″

    𝒊′ = ±[μ′₂/2 1]/(μ′₁-μ′₂²/4)¹ᐟ²

    𝒊″ = ±[μ″₂/2 1]/(μ″₁-μ″₂²/4)¹ᐟ²

    and then
    (a𝒆₁⨢b𝒊′)∘′(c𝒆₁⨢d𝒊′) = (ac-bd)𝒆₁⨢(ad+bc)𝒊′
    (a𝒆₁⨢b𝒊″)∘″(c𝒆₁⨢d𝒊″) = (ac-bd)𝒆₁⨢(ad+bc)𝒊″

    And the two ℝ.extending plane.multiplications
    are isomorphic.
    Therefore, there is
    only one extension of ℝ to ℝ², up to isomorphism,
    and, for that extension, 𝒊² = -1

    ⎛ What I got wrong initially was that 𝒊 ≠ 𝒆₂,
    ⎜ at least, not necessarily equal.
    ⎜ That it's not doesn't matter, though.
    ⎜ All the different '∘' with their different 𝒊
    ⎝ map to each other very neatly.

    Not sure I "got" it all.

    My explanations evolve.
    To a higher, purer state, I hope,
    but to a different state, at least.

    Richard Hachel's question "What is i?"
    is a good one.
    Others will ask it, others have asked it.
    I think I might have, a million or so years ago.

    When I spot another excuse to try,
    I'll likely try explaining again.
    It'll likely be different. Again.
    Maybe even better.

    Thank you for your attention.

    I once did, I guess, a similar thinkthing about
    not necessarily fields, but
    multidimensional numbers alright,
    as n-vectors and
    as "autovariant" nxn matrix families:
    https://www.wugi.be/hypereal.htm

    That deserves more than a glance.

    I'm a great fan of vector spaces.
    So many theorems, so broadly applicable.
    Fourier transforms are rotations in function space!

    You:
    / I called these the "Autovariance conditions",
    | assuring that the matrix family embraces
    | any product of its members.
    | Without these conditions,
    | a random product would “leave”
    | the n-dim matrix family into
    \ the n x n matrix space!

    Perhaps you are talking about
    an n.dimensional subspace closed under
    the usual matrix multiplication?

    Yes,
    it reminds me of how I describe complex numbers.
    For me, "mediating" 2x2 matrices are inserted
    to define the not.the.usual product.
    [a b]∘[c d] :=
    [ [a b]ᵀ𝑴₁[c d] [a b]ᵀ𝑴₂[c d] ]

    [ 𝑴₁ 𝑴₂ ] has eight degrees of freedom, enough,
    we find, to impose field conditions on '∘'

    I wonder what we can get if
    something like that is done with nxn matrices.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From guido wugi@21:1/5 to All on Fri Jan 31 18:00:11 2025
    Op 31/01/2025 om 17:07 schreef Jim Burns:
    On 1/31/2025 6:31 AM, guido wugi wrote:
    Op 30/01/2025 om 22:55 schreef Jim Burns:

    There are different values possible for 𝒆₂∘𝒆₂ = [-μ₁ -μ₂],
    but, as long as μ₁ > μ₂²/4,
    ⟨ℝ²,⨢,∘⟩ is a field extending ⟨ℝ,+,⋅⟩.

    For two plane.multiplications ∘′ and ∘″
    we can map 𝒊′ ⟷ 𝒊″

    𝒊′ = ±[μ′₂/2 1]/(μ′₁-μ′₂²/4)¹ᐟ²

    𝒊″ = ±[μ″₂/2 1]/(μ″₁-μ″₂²/4)¹ᐟ²

    and then
    (a𝒆₁⨢b𝒊′)∘′(c𝒆₁⨢d𝒊′) = (ac-bd)𝒆₁⨢(ad+bc)𝒊′
    (a𝒆₁⨢b𝒊″)∘″(c𝒆₁⨢d𝒊″) = (ac-bd)𝒆₁⨢(ad+bc)𝒊″

    And the two ℝ.extending plane.multiplications
    are isomorphic.
    Therefore, there is
    only one extension of ℝ to ℝ², up to isomorphism,
    and, for that extension, 𝒊² = -1

    ⎛ What I got wrong initially was that 𝒊 ≠ 𝒆₂,
    ⎜ at least, not necessarily equal.
    ⎜ That it's not doesn't matter, though.
    ⎜ All the different '∘' with their different 𝒊
    ⎝ map to each other very neatly.

    Not sure I "got" it all.

    My explanations evolve.
    To a higher, purer state, I hope,
    but to a different state, at least.

    Richard Hachel's question "What is i?"
    is a good one.
    Others will ask it, others have asked it.
    I think I might have, a million or so years ago.

    When I spot another excuse to try,
    I'll likely try explaining again.
    It'll likely be different. Again.
    Maybe even better.

    Thank you for your attention.

    I once did, I guess, a similar thinkthing about not necessarily
    fields, but
    multidimensional numbers alright,
    as n-vectors and
    as "autovariant" nxn matrix families:
    https://www.wugi.be/hypereal.htm

    That deserves more than a glance.

    I'm a great fan of vector spaces.
    So many theorems, so broadly applicable.
    Fourier transforms are rotations in function space!

    You:
    / I called these the "Autovariance conditions",
    | assuring that the matrix family embraces
    | any product of its members.
    | Without these conditions,
    | a random product would “leave”
    | the n-dim matrix family into
    \ the n x n matrix space!

    Perhaps you are talking about
    an n.dimensional subspace closed under
    the usual matrix multiplication?

    Yes, that would be the proper description I think.

    Yes,
    it reminds me of how I describe complex numbers.
    For me, "mediating" 2x2 matrices are inserted
    to define the not.the.usual product.
    [a b]∘[c d] :=
    [ [a b]ᵀ𝑴₁[c d] [a b]ᵀ𝑴₂[c d] ]

    [ 𝑴₁ 𝑴₂ ] has eight degrees of freedom, enough,
    we find, to impose field conditions on '∘'

    I wonder what we can get if
    something like that is done with nxn matrices.

    There you've lost me :)
    Still, my interest now (and since then:) is really the "true" geometry
    of complex functions w=f(z).
    Here's my recent little "paper" on that topic, with all relevant links
    in the references:
    https://www.wugi.be/mijndocs/compl-func-visu.compleet.pdf

    Greetingz,

    --
    guido wugi

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