# Testing string theory

1. Aug 14, 2004

### Mike2

So...
If the mass of a fermion is dependent of the frequency of vibrations of extended objects such as strings or membranes, etc, then wouldn't this frequency (and thus the mass) be subject to gravitational redshifting just as photons are? So shouldn't string/M-theory be just as easy to test as the gravitational redshifting of photons?

2. Aug 14, 2004

### sol2

http://www.airynothing.com/high_energy_tutorial/detection/images/compton_scatter.gif [Broken]

Compton scattering detector

You have to remember the temperature as you get closer to the source. What do these Gamma rays tell us?

http://imagine.gsfc.nasa.gov/Images/introduction/em_same.gif

"
http://en.wikipedia.org/wiki/Loop_quantum_gravity

So from this deduction supplied in last quoted paragraph?

Last edited by a moderator: May 1, 2017
3. Aug 15, 2004

### Mike2

I suppose further that if rest mass is affected by gravitational redshifting, then the next thing to test would be whether the change in frequency/mass only changes by quantized amounts. This would prove the existence of the graviton, right? For the interaction with gravity is by the graviton, and if the particle lost mass, then that energy would have to travel away via the graviton. Or can the graviton assume any energy level? Thanks.

Hey look, they now have a spell checker. Great!

4. Aug 15, 2004

### sol2

5. Aug 29, 2004

### Mike2

Wait... if particles are strings or other extended objects that "vibrate" with some frequency, then it should be affected by the time dilation of Special Relativity. So whatever characteristic of strings or membranes that are determined by the frequency of some vibration should change near speeds approaching the speed of light, right? That sounds like an easy confirmation of string theory, or M-theory. Right?

6. Aug 29, 2004

### sol2

So what is this http://viswiz.imk.fraunhofer.de/~nikitin/course_practicum/applet.html [Broken] that we have been reminded about?

I had been quoting a lot of information on Glast, and that if LQG was supported, how we might find strings falsified( I might have been to harsh here given following link). But you have to realize what Lqg is up against. It works the other way as well.

http://www.lns.cornell.edu/spr/2003-10/msg0055518.html

http://en.wikipedia.org/wiki/Loop_quantum_gravity

Last edited by a moderator: May 1, 2017
7. Aug 31, 2004

### Mike2

A Relativistic test of String Theory

Maybe the title should read: A Relativistic Test of String Theory.

8. Sep 2, 2004

### Mike2

Could it be that no observable properties directly depend on the frequency of vibrating strings? Is the mass of a Superstring determined by the frequency of vibration, or does it depend on the mode of vibration? I suppose the actual mode of vibration is Lorentz invariant.

9. Sep 2, 2004

### sol2

the energy considerations leave a impression........as we look at the microscopic view of the particles nature, this energy leaks into the extra dimensions. Some, like to compare it to a string that vibrates.....

10. Sep 2, 2004

### Mike2

So here comes a vibrating string to collide with a stationary string. Is it a fact that the more these two strings have in common (same frequencies and amplitudes) the more likely it will be that they combine into one string? Is the cross section greater for like particles (or perhaps antiparticle) than for particles that have less in common? If this is so, and the frequency is slowed for relativistic incoming particles/strings, then it might be that the cross section is reduced with high speeds? What do ya think?

11. Sep 3, 2004

### sol2

Is there a way around the M1 to m2 measure to test for dimensional recogniton of M theory. I pose this question here in thispost