Modern and Theoretical Physics

It seems the meeting of particle/antiparticle keeps the violation of conservation from occurring. But if Hawking Radiation is a vast group of particles composed entirely of the one particle that didn't fall into the black hole, then can't we safely deduce the escaping particles won't be annihilated in the near future? Yet if that's the case, has the violation occurred? Another question on Hawking Radiation: it follows that about half of the particles falling into the black hole by that process will be "anti". If so, the black hole itself surely is made of regular particles. So as soon the anti- enters the black hole, shouldn't it annihilate with a random part…

I'm having an incredibly hard time understanding the concept of branes. Kaku theorized that in hyperspace there are multiple universes which result from the collisions between points on oscillating membranes.. But what are these membranes? How many are there? How many types are there? How many dimensions do they occupy? Why do these collisions produce universes?

I was recently involved (though my activities with the Institute of Physics High Energy Particle Physics Group) with the production of a booklet called "Particle Physics - it matters", which is trying to publicise a little why particle physics is a worthwhile thing to study. I would appreciate it if those of you who are interested in this sort of thing could take a look at it and give me any comments. I will be discussing it in an IoP meeting on Monday, so now is your chance to be heard!

Hi, on Oct 3rd/2009 I started posting my proposals. My first revealing of my ideas was on Garret Lisi's forum ( he proposes a Theory of Everything on the e8 gauge structure). Ironically he's a skeptic of string theory but he's brilliant and I can't wait for any replys but the thread is very old and kind of inactive. I have found Harvards forum and my thread is just sitting there dormant for a day now hehe. I am waiting to be registered at Cornell still. You will find amusing that some geek at a big school forum website that hosts Oxford and Cambridge student forums has deleted my thread (same material copied from what I posted at every other forum) because he considered i…

Is Time Travel Possible? "Not all scientists agree but according to Einstein and quantum theory, time travel could be possible. According to Einstein's special theory of relativity, our lives pass more slowly if we travel close to the speed of light. He has also shown that we live longer if we go and live in an intense gravitational field. Einstein has thus opened up the future and shown that it is possible to slow down time for ourselves, leave the Earth and come back to meet our grandchildren or our great-grandchildren. But he has not shown that it is possible to come back! Physicist Steven Hawking has suggested that it is not possible to go back in time because yo…

Hi all. I would like to first offer this disclaimer: I'm not a physicist or scientist. I'm a computer technology professional and an enjoyer of all things involving theoretical physics. With that said, I've been thinking about black holes and their "evaporation" over time and the resulting spew of energy after the black hole collapse. My thoughts about this are as follows: 1. All of the energy ejected as the mass of the black hole decreases was originally captured/ensnared/eaten by the black hole. 2. As the black hole's mass increased, so did it's gravity, and thus it's distortion of space-time. 3. The dip caused by increased the gravity is a g…

For the longest time I thought light (or photons) were both particles and waves. Recently a professor at school told me that it was actually more that photons were not particles nor waves, but instead something new. This new thing does not have any other real life example that we can say it acts as, but has certain properties of both particles and waves, but not all of them. What kind of properties do photons share with particles, and what properties do they share with waves? What new properties do they have that are unlike anything else? Where is the newest research on light going? (I realize these are heavy questions and may have very long answers, but…

I am trying to work out a difficult problem. Atoms are smashed in colliders to release energy. Could this be happening in a black hole? I think it is, I think that all of the matter in the black hole will get destroyed, well lets say the mass will be converted into energy. But their is a problem, I do not know what the pressure is inside a black hole and how much energy would be required to destroy the particles inside. The most massive black hole known (binary pair, in OJ 287) is 18 billion solar masses. I think that would be enough to convert the matter into energy. Any help?

Hi, My first post outside of the 'intro thread' -- not entirely sure this is the correct sub-forum. Question: Are the properties of Infinite Mass exactly the same as the properties of an absolute vacuum? That is: the same everywhere, one state, no events, no time, no temperature, ... what else? I asked this question in '92 and got a 'yes' but, I'm behind the curve and out of date now. Thanks! Ron

Sometimes it is noticed with time that it's not the "(more) exact (but too long) calculation", that is remembered at the end, but more simple, schematic or short, easy to remember, version, (majority memory). For example : -SensiblerQM Postulate : Measurement of (sub)system disturb the system. (We need 5 symbols in english, and 6 in french, 7 in german) instead of long incomprehensible calculations ? or -Relativity 2+1 : instead of sheet-long matrix products with Lorentz boost, a geometrical view : 1/2 angle between both frames of reference space direction [math]\vec{e}_\phi[/math] and [math]\vec{e'}_\phi[/math] is given by : [math]v_\phi/c…

How, if at all, would our perception of time change if the earth was shaped like a crumpled-up ball of paper?

For those who are interested, I have been working on the issue of gravity and force unification. Below is a shortened version of my work so far. I am not taking the time to polish this for this first post so bear with me. The big question in science today is why gravity has not been unified with the other forces of magnetism, electricity and atomic. Electricity and magnetism were united under electromagnetism. The nuclear forces are classified as strong and weak. In these cases, forces are tied directly to energy with the exception of gravity. These forces also fall along the electromagnetic or “light” spectrum – except gravity. I do not believe that gravity is so dif…

OK, so I was thinking about time travel the other day, and basically formulated a kind of logic puzzle: The Primary Assumption: Time Travel is possible. Now assuming that the above is true, here's my scenario: Suppose someone (e.g. Adam) is a normal guy. He somehow travels back in time and meets his mother. Adam then marries his mother and has a child, himself. Now, here's my paradox. If he travels back in time, then he would always have been his own father. I know this "time loop" thing has been proposed before and you probably all already know what it is. Now, unless parallel universes exist, Adam is his own father. Let's say Adam Original's genes are XY. X …

Not what you're thinking At least not quite. Virtual particles wink into existence throughout all of space. Can it be possible in the future to grab and isolate those particles for conversion to usable energy before they wink out again? If so, might it be the ticket to free energy? Assuming of course it takes less energy input to harness their output of energy. Side question: what happens if the virtual particles don't return to the vaccuum energy of space? Does the non-virtual Universe's total energy increase?

Does a black hole have to be spherical?

Hi there, I'm nowhere near an educated Physicist, but I have a healthy interest in the subject. So according to M-theory, we're all living on a membrane, next to a lot of other membranes, and nothing can escape this membrane, except Gravitons, which explains why gravity as a force is much weaker than the 3 other forces. Then I've also read that the Higgs boson may be the elementary particle that gives mass to all other particles (quarks and leptons) and the W and Z bosons, and that there is, hypothetically, a Higgs field in which our Universe (and if there are any, all other universes) is completely submerged. String theory says that gravitons are closed s…

A supersonic shock wave starts at the nose cone of a craft breaking the sound barrier. That shock wave is not limited to the surounding craft but travels in a cone shape outward. These shock waves travel outward untill it hits the ground is where we get the ( Sonic Boom ) that can shatter windows. But a coned shockwave also travels skyward unill it hits the clouds which you then can see the waves travel in a striaght lines as fast as the jet. A shockwave wave can travel for miles untill it hits a target as earth or cloud cover. I'v seen that happen and am a withness to visibly see a shockwave.

i was intrigued by how to solve this. the phase velocity of ocean waves is sqrt(g*lambda/2*pi) where g - acceleration due to gravity, lambda is the wavelength of the wave. The question is find the group velocity. I tried many things but was not able to get to a proper answer. Any help?

I don't know if this is well-known, but I have a nice geometric realisation of the N=1 supersymmetric algebra in terms of the Lie derivative along a vector field of differential forms over a (super)manifold. Let [math]M[/math] be a (smooth) supermanifold and let us work in local coordinates [math]\{x^{A}\}[/math]. Here we have [math]x^{A}x^{B} = (-1)^{\widetilde{A}\widetilde{B}}x^{B}x^{A}[/math] where the parity is [math]\widetilde{A} = 0/1[/math], i.e. bosonic and fermionic coordinates. From now on by manifold I mean supermanifold. Over the manifold [math]M[/math] we can build the two natural bundles [math]\Pi TM[/math] and [math]\Pi T^{*}M[/math]. Let us equip…

I was watching the tube on science. The program showed ( Two Opposite Branes ). Why is there two and not just one ?. The two curtains of Brane therory i saw looked as two opposites rubbing against each other like a Plus and Minus on a battery currant flow. Can that anomoly be like a Male and Female ? to create the singularity ?.

Yes, I did it, after 16 years I have solved the secret of the entire universe. The secret involving the unification of gravity with the rest of the fundamental forces. In short, I have solved the Theory of Everything!! Do you want to know what it is or how I did it?

There is something that I have been wondering for quite a while now about Einstein's theory of special relativity; basically it is this. According to Einstein it is impossible for anything to travel faster (or even at) the speed of light because as an object approached the SOL (speed of light) the energy required to move it even faster increases exponentially until it reaches infinity at the SOL. But what I don't understand is this; lets just for arguments sake say that Einstein was wrong about the whole "mass increases approaching the speed of light" thing. If I'm not mistaken it would still require an infinite amount of energy to make something move faster than the…

actually wen i first entered the forum i saw a name appear lepton now its quark? well i think its got 2 do soth with atomic physics. can somebody tell me what those are? both in reality as well as wht we are meant here?

nucleus of an atom is the densest part for much of the rest is a vaccum. still density of nucleus is not as great so as to even stop lights to escape. does it mean within blackholes nucleus gets squeezed for any other arrangement i suppose the volume will be greater. if soth can be squeezed=> there must be some things within it too. ie protons etc are not fundamental. am i right by any chance? please explain.

i want to know how to measure length in relativistic mechanics. i mean if length is some times of a particular value of length ie what we call standard length why does it change/ appear to change when someone moves with speed comparable to the speed of light. i got the answer that since the concept of simultanity changes length seems different in two different reference frames one moving with a velocity not zero relative to the other. my question is what length has got to do with simultanity?