String theory Definition and 782 Threads

I've heard that that origin of String Theory was in Gabriele Veneziano's analysis of the Euler beta function in relation to the strong force. I was wondering if anyone could refer me to a paper or derivation describing how this function ended up describing particles as strings.

String theory requires 9 spatial dimensions, M-theory 10. One followup to Verlinde's paper is this: http://arxiv.org/abs/1002.0488 Hidden symmetries for thermodynamics and emergence of relativity Liu Zhao (Submitted on 2 Feb 2010) Verlinde recently proposed an idea about the thermodynamic...

I'm taking an introductory string theory course which focuses on bosonic string theory. The lecturer says to include fermions supersymmetry must be included (aka. superstrings). If we face the event that the LHC fails to find any supersymmetry at TeV scale and the physics community lose faith in...

It seems to me that string theory is a highly complex way of dealing with the need to avoid zero distances in our mathematical description of the physical world. Wouldn't it be much easier to just say let's use 10^-25cm as a limit and not allow anything to get closer than that in our...

I know the main points of string theory, but can someone tell me where the evidence is that it could be true?

In string theory, what are the fundamental properties of a string? Is the tension in the string a constant at all points on the string and the same in all strings? Is the string "labelled" with fields/spin/etc along its length? How about "velocity"? Is each 'bit' of the string labelled with...

Hi there, I 've recently looked at how the Nambu-Goto action of an open string can be derived from the proper area of the parameterised world-sheet, in the form of either the derivatives of space-time coordinates or the determinant of the induced metric. However, may I ask what are the...

In string theory, a solution involving flat 10D space seems like a valid solution. The Universe could be described by a solution that is 10D space, all large and flat. Of course for string theory to describe our universe, 3D remain large and flat, and 6D or 7D are curled up in a Yau Calibi...

What role does "torsion'' play in string theory? In general relativity we assume that connection is torsion free. However from a purely geometrical viewpoint, the concept of torsion can not be ignored (theoretically) and in string theory, it is said that "torsion" does play its role. Can...

This might be a noob question, so excuse me if I'm beating a dead horse. I'm trying to wrap my head around string theory. If it is how the universe operates, is there such a thing as matter? It seems that everything at its most basic form is just energy. Is this true? Or am I missing a...

http://www.infocobuild.com/education/audio-video-courses/physics/string-theory-cern.html This brings some video lectures on string theory from http://cdsweb.cern.ch/" - introduction to string theory, string theory, string theory for pedestrians etc.

Iv'e scene the documentary about string theory and i just have a few questions about it.(laymen terms) : 1.How does string theory contribute to a unified field theory? 2.Is matter really made of "vibrationg strings"? 3.What does string theory actually mean or what has been the impact...

Is Asymptotic Darkness explicitly known to be realized in string theory?

What makes the strings in string theory "vibrate"? Does string theory include or say what is responsible for making strings vibrate? Also, why do the strings not all vibrate in the same pattern; what makes a string "choose" one pattern over another?

Could the higher dimensional spaces of string theory be used by point particles? Take the idea of extra dimensions of string theory and use point particles instead of strings. Point particles need some type of internal degrees of freedom? Thank you for any help.

Hi! When quantum mechanics was established it allowed us to do things that we could not do before. What would string theory allow us to do? Let's say that string theory was confirmed -- tests showed the projections string theory made were correct and now string theory was accepted. What...

Hi, I just joined this forum a few minutes ago because I'm thinking of joining my high school science research program to research string theory. For those of you who don't know about the programs, basically you research something for three years and then you enter it in the Intel Talent...

What is the best review article, published in a peer-reviewed journal, introducing string theory?

How do String Theory and Quantum Entanglement mix?

At what level (graduate, PhD, etc...) do people start learning theories, such as String Theory and Loop Quantum Gravity?

Hi, What is the absolute best grad schools in the US or Europe for String Theory, M-Theory and LQG? I tend to learn better in a classroom environment, so I'm sort of looking for a grad school which actually has relevant courses, and not just a European-style research university where I...

Since now time is 2-dimensional, coordinates of points X\mu are dependent on both (\tau1, \tau2), and if \tau2 is infinite, it's a open string; if \tau2 is finite, it's a closed string. How do you think so?

My teacher told me that in my essay I need to briefly describe string theory (because I'm talking about how the LHC is a good test for string theory) and by briefly she told me 1 sentence. If anyone could tell me how THEY would describe string theory in 1 sentence that would be much...

Hi, I am trying to understand relations between Homology/CoHomology and Homotopy group..I am familiar with Hurewicz Theorem but I need something more general. I hope that you can help. Thanks, Lala

Does string theory imply time as a dimension that can run in more than one direction or is it asymmetric?

I have watched numerous shows about physics and I am curious if I understand gravities apparent weakness due to 11 dimensions correctly. The way I made sense of it was by picturing myself at the bottom of a steep hill. At the top of the hill I saw a huge amount of water coming down hill. It...

so i came across string theory and i don't understand (if your going to go along with it) why it is tiny strings that make up the universe and why exactly do they have to exist in more then 4 dimensions?

Topological string theory is a description devoid of metric and hence is background independent and everything emerges from pure topological considerations. This should put it at the front of all other candidate string theories, but that is not the case (it is certainly considered important, but...

I'm a physics undergraduate (2nd year), and I'm just learning the basics of Quantum Mechanics. As you would expect, I've been fascinated by the elegance and...paradoxes involved. My question here is about the phenomenon of entanglement. I know the mathematics of it, but when I asked my...

I have a computer science background, so I don't know about this. Can somebody give me some recommendations on good introductory books about -String Theory - Wormholes -Black holes etc. I'm looking something for academics, not for general public. So maybe books for 1st year graduate...

The Coming Revolutions in Fundamental Physics--as seen by string-master David Gross http://seminput.aei.mpg.de/more_info.php?which=2478&talk=index ==quote== Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut The Coming Revolutions in Fundamental Physics Wed 7 Oct 2009...

Does string theory predict additional long range forces gravity EM? One of the most touted features of String theory is that it correct predicts and even requires 2 infinite long range forces, gravity and E&M. I've heard that string theory though also predicts additional non-observed long...

Firstly i am under educated in physics, that said i have a great interest in physics, this interest sends me a drift with many questions. As many questions in philosophy i seek to start at the beginning and develop a theory from there (or at least what i thin k is the beginning). For...

If you have a guitar string and you pluck it nothing happens. Not unless it is tensioned by pulling both ends tightly. In string and brane theory do the strings have something that keeps them tensioned? Or don't they need tension to maintain vibrating; unlike normal strings? Are they free...

Is gravity a particle field on spacetime or is it the geometry encoded in spacetime itself? Since strings is 10-11 D, does a mass-energy object curve all 10 dimensions of spacetime or only 4 dimensions? Is there a problem of time in string theory as there is in canonical quantum gravity? What...

What does string theory have to say about this and how has string theory changed cosmology in terms of verifiable observational predictions?

http://www.forbes.com/forbes/2009/0921/opinions-peter-woit-physics-ideas-opinions.html Princeton's Witten declines to discuss Woit, saying in an e-mail that he prefers to debate these issues only with "critics who are distinguished scientists rather than with people who have become known by...

Spacetime is 3D + 1T = 4D Is spacetime in string theory 4D as a result of compactification, or 12D, 11D+1T?

Would someone please give me the rundown on the String Theory? I have The Elegant Universe novel and I've been stressing to understand this theory but I've hit a few dead ends. Could someone please enlighten me? Thank you kindly

Am I correct in thinking string theory has an infinite number of terms so to prove finiteness to the first order means proving one (or the first) term to be finite? If so, then how can we ever prove an infinite number of terms? And what exactly does it mean to say, or prove, something is...

I have, for a couple of weeks, been looking up what string theory is all about but i can never actually really grip it. Is there anyone one out there who can give me a simple explanation of it?

"String theory is not science!" So there seems to be a lot of people bashing String Theory for not being real science (real science being theories with predictive/explanatory power). For instance: https://www.amazon.com/dp/061891868X/?tag=pfamazon01-20...

The historic roots of string theory are in an explanation of the strong force. Nowadays QCD is the accepted theory of strong force. But having heard several lectures on the large N limit (SU(N)) of gauge theories it seems these theories start to looklike string theories in this limit. I believe...

http://www.eurekalert.org/pub_releases/2009-07/lu-pro070309.php Well, according to this article, at least. http://www.sciencemag.org/cgi/content/abstract/1174962 Just thought I'd share. Problem is, they didn't entirely describe high temp superconductivity. O well.

I've heard it said that to include a quantum theory of gravity in string theory that the model must include extra dimensions to explain the apparent weakness of gravity. First off, why? couldn't you just as easily say the universe is bigger than we thought and that's why gravity is so weak? And...

Hey all, first post here. I had the opportunity recently to ask Steven Weinberg a question that the physics professors at my university didn't have an answer to. In short, Weinberg said he couldn't understand where I was going with my question. My heart broke as I obviously wasn't able to convey...

I am reading The Elegant Universe...and I have bumped to possibly the first part of the book that I can not understand. When an electron and a positron pop out of existence, they soon annihilate each other with a "bang"...emitting a photon. If fundamental substance of universe are...

Up to now I have learned that matter particles (aka Leptons) were point particles with no physical size/extension. As a matter of fact, it appears that most (including many here based on responses to one of my earlier threads: https://www.physicsforums.com/showthread.php?t=301495") apparently...

How useful is the framework of minimal Conformal Field Theory (ie. CFTs with finite primary fields) in String Theory? From what I have come across, I have only seen its usefulness in studying toy models of minimal string theory.

Hidden dimensions of string theory "hiding" in 4D spacetime? Could the hidden dimensions of string theory be "hiding" in 4D spacetime? Thank you for any thoughts.