Speed of Light question

[Pinotage]

I thought M Theory was supposed to have smoothed over the disconnect between Relativity and Quantum Mechanics?


also non-physicist glass.

In theory, mostly. Unfortunately, very few of the concepts in M-theory have actually been proven. While the theory postulates many things, such as the existence of gravitron particles and its supposed properties etc., until somebody actually proved it, it's little more than a theory. I believe the new Hadron collider will hopefully generate enough energy to detect various new particles, such as the heavy super particles, that may give support to M-theory (a form of string theory where the world is not only made up of vibrating strings, but also membranes, called branes).

It is also, unfortunately, a horribly complicated theory, and not easy to use for predicting things, but yes, it does smooth over some of the issues between quantum mechanics and relativity.

Pinotage

 

[Pinotage]

That would mean that light has no time component velocity right? So from a photons point of view, it exists for zero time? Freaky.


glass.

Relatively speaking, yes. A person travelling at the speed of light, or a photon, would be considered to have a zero time component relative to an observer. The person travelling at that speed, however, would experience time normally.

Pinotage

 

[Nellisir]

I believe the new Hadron collider will hopefully generate enough energy to detect various new particles, such as the heavy super particles, that may give support to M-theory (a form of string theory where the world is not only made up of vibrating strings, but also membranes, called branes).

Mmmmm, branes.


Nell.

 

[fuindordm]

Mmmmm, branes.


Nell.

Watch out for those zombie physicists!

The term was originally N-brane, meaning an N-dimensional generalization of a membrane, meaning an N-dimensional surface in the 11-dimensional space of string theory.

The Elegant Universe, by Green, is a very enjoyable book on string theory that is accessible to people of all backgrounds. Not only are the predictions of the theory still
untestable in the lab, humanity's math skills aren't yet really advanced enough to treat it
fully.

The LHC might be able to test some predictions of string theory if we're lucky, but just identifying the Higgs particle would be enough to make all the physicists of the work squeal and clap their hands like little girls. I'm not holding my breath for more from them.

Ben

 

[Umbran]

I thought M Theory was supposed to have smoothed over the disconnect between Relativity and Quantum Mechanics?

None of the theories that try to connect gravity and quantum mechanics have yet to make one very important milestone - verifiable predictions.

In order to be considered a viable candidate, a theory needs to do more than "smooth over" a disconnect. It needs to make testable predictions that other theories don't make. The various brane, string, and holographic theories still don't do this, even though we've been working on the problem since the 1970s.

 

[Desdichado]

Above, you fall into the trap of thinking about light as a normal physical object. If you toss a ball near a massive object, it'll speed up and slow down as you describe, but light is not a rubber ball.

Exactly. Photons have no mass, so they are not affected as massed(?-is that the word?) particles would be by gravity.

 

[Desdichado]

www.pbs.org has a lot of good articles on black holes. You can do a search for "black hole" to find all kinds of stuff.

Once upon a time I found episodes of, I though NOVA, regarding black holes and physics topics like quantum physics, but I can't find them now. It might not have been NOVA, but I thought it was.

If it's still accurate. How old is it? There's been a lot of changes in our theoretical picture of the universe over the last few years, starting with M-Theory, which has already been mentioned here.

 

[Harmon]

JD- photons aren't effected by mass?

Is that true?

 

[Desdichado]

No, they don't have mass, so they're not affected the same way as particles with mass. Notably, that they don't slow down when subjected to gravitational attraction. They can however still be diverted by the gravity well of large mass.

 

[Harmon]

No, they don't have mass, so they're not affected the same way as particles with mass. Notably, that they don't slow down when subjected to gravitational attraction. They can however still be diverted by the gravity well of large mass.

Okay, my misunderstanding. The other way would have had some intentesting implications