I have a question about the super string theory!?

Question

I recently learned about string theory in class, and i was just wondering about a thing or two. If the so-called "strings" are massless, then where do they get the energy to vibrate, stretch, and expand in space? i thought e=mc^2?

Answer 1

Never liked super string.

Answer 2

Just to expand upon what others have said...the strings aren't completely massless because, as you correctly pointed out, everything that has energy has mass and vice-versa. The only thing is, their mass is so exquisitely small that it does not affect the calculations and we can just assume it's zero. The same is true for the photon--if you're learning about string theory then I'm sure you're very familiar with the photon and how it travels at the speed of light, and no object with mass can travel the speed of light. However, similarly photons are not entirely massless (they do carry some energy) it's just that their mass is so incalculably small that it's pointless to take into consideration. And if a photon, which is numerous times larger than a super string, has no mass as we define it, then a string has even less mass than we define it...:) Hope that helps a little.

Answer 3

If strings were massless they would have no energy because
V=0.5*m*v^2, not e=mc^2. Something massless cannot said to have kinetic energy, but I am completely unfamiliar with most string theory. E=mc^2 is the conversion of mass to energy.

Answer 4

The "vibrations" in Super String Theory are really quantum fluctuations, meaning that they are the measures of the innate probability that the "strings" will be found in any particular state, not vibrations as we would expect from, say, a guitar string.

Remember that the theoretical "strings" are subject to Heisenberg's Uncertainty Principal. As such, they cannot be continuously measured to any substantive degree. So, the "vibrations" represent the likelihood that, when measured (the more accurately we measure position the less we can know how the particle is moving), it will appear in state x.

Answer 5

They are not always massless, however the mass is so small that doing calculations on them with no assumed mass makes the work easier and just as accurate since most string theory calculations rely on approximations anyway.

Answer 6

String theory is the conventional term used to describe a set of models of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. For this reason, string theories are able to avoid problems associated with the presence of pointlike particles in theories of physics, in particular the problem of defining a sensible quantum theory of gravity. Studies of string theories have revealed that they predict not just strings, but also higher-dimensional objects.

Answer 7

First, I easily have lined the valid internet internet site on string concept (link decrease than). 2d, the e book "The stylish Universe" by employing Brian Greene (he's a string physicist) is an marvelous creation to thread concept for the non scientist. Einstein did no longer create string concept and easily it grew to become into attempting to describe some flaws or wholes in his factors of the universe that led to string concept. no person individual (as that 3 particle physicist observed the same problem on the same time and then rapidly there have been 5 distinctive theories of strings (now blended in great string or M-concept by employing yet yet somebody else) created string concept. to handle your question possibly no longer. Einstein could no longer even settle for the findings of his very own artwork that debris have been entangled (a elementary of quantum mechanics) by way of fact it grew to become into no longer explainable in classic words of physics. additionally, the dimensions (a minimum of 11 might desire to exist for great string concept to be genuine) that are theorized are all on the sub atomic (no device customary to guy can degree something as small as they are pronounced to be) point. So, in concept once you wave your hand each time you're passing with the aid of 11 dimensions yet you do no longer word it by way of tiny effect. So, different dimensions are in comparison to parallel worlds the place each thing exist on the same point yet purely out of section with us. in case you're perplexed you have began to hold close great string concept in case you think of you already know or can are conscious of it very virtually each physicist working interior the sphere permit you to grasp it quite is a advantageous sign which you are not getting it. Edit: yet keeping questioning and asking questions. I constantly discover your questions stimulating and that they bring about further questions that could desire to be researched. Psi

Answer 8

some strings are not massless, they are called the gravitons.