Calculate between [-epsilon,epsilon]

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In summary, the conversation discusses the integration of -(p(y)f(y)')'=m^2w(y)f(y) with given functions p(y) and w(y) and a variable y between [0,infinity[. The question is whether to calculate the integral between \int^{epsilon}_0 or between [-epsilon,epsilon], and the integral itself is given as \int^{\epsilon}_0(p(y)f(y)')'dy. It is noted that f is not continuous at zero and the result is given as f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}. This problem is found in equations (3)-(6) and (10) of
  • #1
alejandrito29
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i need to integrate

[tex]-(p(y)f(y)')'=m^2w(y)f(y)[/tex]
where
[tex]p(y)=e^{4ky}(1-4ak^2)[/tex] and [tex]w=-4ae^{2y}k\delta(y)[/tex]

but y between [0,infinity[

¿i calculate between [tex]\int^{epsilon}_0?[/tex] or ¿i calculate between [-epsilon,epsilon]?

but, what is??

[tex]\int^{\epsilon}_0(p(y)f(y)')'dy[/tex]

whit f is not continuous in zero


the result is
[tex]f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}[/tex]
 
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  • #2


alejandrito29 said:
i need to integrate

[tex]-(p(y)f(y)')'=m^2w(y)f(y)[/tex]
where
[tex]p(y)=e^{4ky}(1-4ak^2)[/tex] and [tex]w=-4ae^{2y}k\delta(y)[/tex]

but y between [0,infinity[

¿i calculate between [tex]\int^{epsilon}_0?[/tex] or ¿i calculate between [-epsilon,epsilon]?
I have no idea what you are talking about. What are yu integrating? If you are talking about the integral above, if it is given as a definite integral, you use whatever limits of integration are given. If it is given as an indefinite integral (anti-derivative) you do not use any limits of integration.

but, what is??

[tex]\int^{\epsilon}_0(p(y)f(y)')'dy[/tex]
By the Fundamental Theorem of Calculus, the integral of the derivative of any function is that function:
[tex]\int^{\epsilon}_0(p(y)f(y)')'dy= p(y)f(y)' [/tex]


whit f is not continuous in zero
If f is not continuous at zero, then it is not differentiable at zero and the integrand above does not exist at 0.


the result is
f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}
Since you haven't actually stated what the problem is, I have no idea whether that is correct or not.
 
  • #3


HallsofIvy said:
Since you haven't actually stated what the problem is, I have no idea whether that is correct or not.

[tex]f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}[/tex]
this problem is in eq. (3)-(6)...(10)
of:
http://arxiv.org/PS_cache/hep-th/pdf/0311/0311267v3.pdf
 
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FAQ: Calculate between [-epsilon,epsilon]

1.

What does "[-epsilon,epsilon]" mean in a calculation?

In a calculation, "[-epsilon,epsilon]" refers to a range of values between negative and positive epsilon. Epsilon is a symbol used in mathematics to represent a very small positive quantity, often used in the context of limits and approximations.

2.

How do I calculate between [-epsilon,epsilon]?

To calculate between [-epsilon,epsilon], you will need to have an expression or equation that involves epsilon. Then, you can substitute different values for epsilon within the range of [-epsilon,epsilon] and solve for the resulting values. This can be useful in finding approximate solutions or determining the behavior of a function as epsilon approaches zero.

3.

What is the significance of using "[-epsilon,epsilon]" in calculations?

The use of "[-epsilon,epsilon]" in calculations allows for a more precise and accurate representation of values that are very close to zero. It also helps to avoid errors and uncertainties that may arise from using an exact value for epsilon.

4.

Can I use any value for epsilon in "[-epsilon,epsilon]"?

Technically, you can use any value for epsilon as long as it is a very small positive quantity. However, it is common to use a standard value for epsilon, such as 0.0001 or 0.00001, to ensure consistency and comparability in calculations.

5.

How is "[-epsilon,epsilon]" related to the concept of a limit?

The concept of a limit involves determining the behavior of a function as the input value approaches a certain value, often represented by epsilon. By using "[-epsilon,epsilon]" in calculations, we are essentially considering a range of input values that are very close to the limit value, allowing us to make more accurate approximations and predictions.

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