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We are therefore in a logical impasse unless you redefine what you mean by the term universe. This is because the term universe means the total sum of everything that exists and therefore it is impossible for anything to be "outside" the universe.
The simple answer to the question could well be no. The universe as a whole does not have an energy because the positive energy of atoms and radiation that forms most of the universe we know could well be exactly (or almost exactly) balanced by the negative energy of the gravitational field.
Sorry I do not understand what you are saying. Please explain it to me in your own words using simple language. I will Google that topic but I feel qite strongly that in these pages you should strive to use language that is easily understandable by most people and in particular explain things where they use specialist technical terms.
The best popular book that I know on the "tmeless" universe is "the end of time" by Bulian Barbour. This shows that time and space as an emergent property of a universe that in effect explores all possible configurations of itself and finds that certin squential possibilities are more probable and this leads to the development of universes with space time properties like our own.This does not mean in any way that our concepts of time are invalid in our environment. The universe that we are aware of is a dynamic structure with energy and energy gradients. it is logical that the total enery of the bulk (everything that exists) could well be zerom any theoretiians suggest that our universe may have grown from a small "seed" universe and I have suggested elsewhere (new theories) how tiss might be possible
I agree with you that space and time are a variable feature of our universe but I do not think calling it "an Illusion" implying that there are ways in which it may be possible to break the rules is a very likely probability. If it was our universe could not be stable. My opinion is as I have said elsewhere our universe is one of a vast number of broadly similar universes that have "evolved" from the bulk (as defined earlier) All these universes are essentially physically very small and contain a relatively small amount of energy as a seed but gain their space time and energy from the conservation of energy and angular momentum during their gravitational collapse. Each universe can seed vast numbers of new universes almost without limit like a fractal. The evolution process is favoured by others notably Lee Smolin who was probably one of the first to describe this concept in his book "Life of the Cosmos" ISBN 0 297 81727 2 The main evolutionary drive for universes is to gradually develop the physical laws to maximise the existence in time and space of a universe because that makes such universes much more probable to detect in any random selection of universes most of which would only last for very brief periods in a very small area.I am not in favour of the concept of totally random selection of physical laws during the spontaneous symmetry breaking during initial expansion of the space time dimensions the randomness is biased in directions defined by the end products of variations in the physical laws which because of quantum mechanical uncertainty become more diffuse at high energies.
I do not disagree with your quotation. This does describe what happens in our universe which is the only one we will ever be able to experience and/or receive information about. The multiple universes I am talking about are entirely separated and never ever communicate with each other except that if you fall into a black hole in one you end up in a different universe for ever.Multiverse concepts were developed to get round the problem of the extremely finely balanced nature of our physical laws in a an environment where physical laws could change as a result of the initial "set up" parameters of any particular big bang type universe.My hypothesis is that like the ecosystems on this planet the physical laws have evolved through many generations of universes to be closely similar to those we see today in our universe because any universe seeds other universes with small quantities of it own matter. gravitational collapse and the interplay of the laws of conservation of energy and angular momentum do the rest!
Two-way interaction, as in time?
>Does the universe have an energy?If you mean is the value of the total energy of the universe non-zero then nobody knows. Perhaps it is zero. I suspect that it is but can’t say for sure. If you mean is the large scale average energy density of the universe non-zero then no.>How can the universe have an energy? I don’t understand the question. To me that’s like asking “How can the Earth have mass?” > I question this, because for a system to have a defined energy, there needs to be an > observer.If it were true then one cannot say that energy existed before observers existed and I disagree with that assertion. It is my opinion that the universe existed before man did. >For the universe to have a defined energy [i.e. a specific quantity] - then according to >the laws of quantum mechanics there needs to be an observer sitting outside of the >realms of space and time.This is one of those fuzzy areas of quantum mechanics. One who is well versed in the philosophy of quantum mechanics is in a better position to address your concerns. Two interesting articles on the subject areQuantum Mechanics and Reality, by Bryce S. DeWitt, Physics Today, Sept. 1970 pages 30-35
This doesn't mean the energy we see everyday; this energy we see is in the form of real energy and real matter. The potential words of statistical probabilties run rife, but we don't see it. In a sense, measurement of energy in physics is essentailly important. If you study the energy eigenstate of a Hamltonian, you will find that observables are involved, and energy which has not been perturbed by measurement can remain in a ghostly superpositioned state.
'Sup dudes and dudettes. [O8)]I was trawling the web, looking for a site explaining (in more accessable terms than wiki-wackymath-pedia) how large astronomical distances are measured, when this site, and this debate, caught my eye. I hope I can contribute something worthwhile to it!I've read through most of the posts concerning your 1st question, Mr Scientist, and I'd like to jump straight to it. I'm not entirely sure what you mean by 'does the universe have energy?' as there are conflicting answers depending on the aspect of the question you emphasise in different posts.If you mean 'Is energy a property of the universe?' I'd say yes. Energy is the potential an object has to do work. As there exist paths the object can move along in the universe (by observation), and as there exist position-dependent forces (by observation), by E = ∫ F(x) dx energy exists insofar as it can be assigned a value. I'm not sure how much experience you have with calculus and path integrals; that equation's the first thought that popped into my mind!However, if you mean 'Is the total energy of the universe zero?' I'd say no. E^2 = (p^2)*(c^2) + (m^2)*(c^4)The total momentum of the universe is zero, because it must be a constant (it's conserved) and we haven't yet observed any preferred direction to the universe. The total mass of the universe is positive* as we haven't observed negative mass; thus the total energy must be non-zero. You've mentioned virtual particles previously. Bear in mind that 'virtual' implies we cannot observe them, and that they suck the energy equivalent of their mass out of the ground energy state, adding nothing to the actual mass of the universe.Yet again, if you mean 'Can I measure/observe/decohere all energy states in the universe from inside it?' I don't see why not, in principle. Measure almost every particle in the universe yourself; get a friend to measure those making up you. Having an observer making a 'time' measurement, though, would immediately muck up your data due to the energy-time uncertainty principle. I'm afraid going into a detailed discussion of what a 'time' measurement is would require at least a degree in physics and several reams of text; pretend you're measuring the position of every particle instead and that an observer mucks it up with a momentum measurement, allowing you to picture the effect of the space-momentum uncertainty principle.Variance(x) * Variance(p) > 0Incidentally, you'll never know the exact value anyways (for x and E, for the universe and each particle) as the variances cannot be 0. Each particle wavefunction will probably intermix and form superpositions straightaway anyway if you do these kinda measurements on a large scale, as gravity becomes important. No-one knows how 'fast' this happens, or what role gravity plays exactly, because as far as quantum mechanics is concerned time is a background upon which events play themselves (it's not an observable) and gravity doesn't exist!If you find an answer to that, let me know *Some theories posit that dark energy, the thing causing the expansion of the universe, may correspond to negative mass, but at the moment they're unproven and are thus speculative at best.