Locrian

That word "prove" is being poorly used here. It should just be noted that Goedel's Theorem does not affect the validity of using mathematics to predict observables in any way. Until someone shows otherwise - which they won't, if you know anything about the theorem and physics - then it has no place in a conversation about physics.

I see where you are going, but allow me to make a counter argument. Einstein spent the last two-thirds (or so) of his career as a physicist producing absolutely nothing. His primary "contributions" during that time were to make arguments that were shown to be incorrect (Hubble, EPR). The areas he was wrong in and troubled by have progressed, and the biggest areas he felt were worth working on haven't made significant progress since he died. Frankly given his irritation with extensive mathematics it's hard to imagine him working in either cosmology or GUT's these days. So who knows? You could make a case that we've been better off letting someone else use the space Einstein would have taken up.

No, that's exactly what superposition doesn't say. Superposition states that a state function is made up of a linear combination of all (orthonormal) eigenstates. It does not say it is one eigenstate and you don't know which.

The best theory ever? I'm not sure what that means, but I am sure that there needs to be a reality show about it. We could put all the great theories in a really small apartment together and see which one predicts the ensuing hilarities the best.

Yea that's a mistype, thanks for the correction. You have the wrong person listed as the quote though somehow.

No one is quibbling over anything. You misinterpreted and misrepresented what I wrote and I responded.

Atheist, looking closer I think what you were writing may have been an example of why that thinking is wrong in response to Tim, and therefore not meant to be an argument why it was right. If that's the case I'm sorry I didn't pick it up quicker.

Yes, contrary to what many uninformed people would have you believe, there are new models constantly being introduced in most of science. This includes cosmology. However, also contrary to what these same uninformed people would have you believe, these new models are generally inferior to the most recent big bang models. I did a quick search on arxiv and turned up the following preprints. I've only glanced through them, so I'm not sure how useful you'll find them all, but at least the first should prove interesting to you. New trends in cosmology. A cyclic universe scenario. An informal introduction to the cyclic universe. Another alternative model.

To repeat what swansont said, it's primarily the geometry. Then you must consider the material the sides of the cavity are made out of - are they solid? Are they covered with thin films? Also consider any material that fills the cavity.

The phrase "instantaneous velocity" did not have anything to do with universal gravitation. How you put these two together is beyond me, but you need to focus on the content of my post. No it isn't. I can conceive of many things. Some are real, some aren't, but you telling me what I can and can't conceive of is absurd. Please keep your comments related to something other than what I'm capable of conceiving of. This is untrue. You assumed that when I wrote "vacuum" I meant something absolute. I did not. Please do not assume I mean absurd things without at least checking with me first. Just because you have an absurd definition of "vacuum" does not mean I do. Nothing you wrote had anything to do with the content of my reply to Atheist.

No, it would not be considered because it is not the same subject as the rest of the group would be adressing. When scientists discuss faster than light travel, they aren't discussing whether you can beat a photon to a destination. They are discussing whether your instantaneous velocity can be greater than c in a vacuum. Your thought experiment in no way suggests that this can be possible. Whoops: See my last post

As I posted on physicsforums, I'm totally stumped as to why oldtobor and nemata are having the exact same, cut-and-paste conversations on both forums. That combined with oldtobor's posting history makes me think something funny is going on here.

Let's say you have two photons in an entangled state. When you measure the spin of one, the entangled state function that describes them is no longer in the original superposition, and you thereby know the spin of the other. This happens instantly. When one part of an entangled state is measured, you must conclude the state function of the other is instantly different than you would have described it just before. However, this cannot be used to instantly transfer information.

Thanks for the link!

Aha! There's your mistake! You assumed that because the object isn't moving in space, that it is prefectly still. In GR you have a non-euclidean space-time manifold. You have to consider all the components!

Not every reference fram is equivelent, only those with constant velocities. The earth is accelerating in a couple of important ways. I'm not sure how to answer the question concerning how the earth is effected by its moving through space. For instance, we end up at different points around the sun and sometimes other planets pass between us and the sun. But I'd think that would be obvious. So what do you mean?

See my reply on physicsforums.

So true.

Coffee? What you are asking for fate sounds like a liquid crystal display, or LCD screen. They are clear until you pass a current through them, at which point they become opaque. So it is a controlable change.

Hah. Doh.

Well that's relatively easy. In a well constructed chamber with a good power source the size of your plasma will be inversely proportional to the pressure and directly proportional to the power. We use these facts to control the size of our plasma ball and the temperature of our substrate daily. However, I noticed you were considering this for fusion power. I believe there are technical barriers to this, probably not the least of which is getting a powerful enough microwave source. As an experimentalist I can give you lots of general knowledge about what's its like working with hydrogen & methane plasmas, but I know very little about applying this to fusion power.

If you find yourself still interested in this topic, I'd like to highlight my suggestion to go look at different laboratories and see what they are studying. Here are some links, just for fun: North Carolina Chicago Berkeley U of Central Florida Iowa Auburn I just did a search on yahoo for "physics departments" and tried to mix in some smaller places with bigger ones. Click the link and go to "research." Most have some information on why they are studying what they are and lists of papers you can read to further explore the topics.

And your interpretation of the questions 1) So..what are the problems in physics exactly? (from the title) and 2) I would like to know what scientists are searching for, and what about (from the OP) as "what are the most interesting questions in physics" (my emphasis) is also exceptionally flawed. That is simply not one of the questions raised, although it may be related. The poster wanted to know what the problems are in physics and what scientists are searching for. He recieved some answers, but the vast majority of scientists working in physics don't work in those areas. Therefore the answers he recieved weren't wrong, but were incomplete. I also mentioned they may be misleading. Some members of the public have taken lists such as were given to him originally (where all problems listed are HEP, gavity or theoretically related) as to mean those are the most important questions or issues in physics. There is no good argument to be made that this is true. Therefore, I worried that he may also be mislead, even if it were in a topic that wasn't his direct question.

Certainly as good as. I'm not sure in what way it would be better. What are your goals?

Swansont answered your question correctly. However, if you are considering using microwaves to generate a plasma, choosing that frequency may not be your best option. The choice of frequency actually more often depends on your cavity size and resonance condition and what frequency power supplies are available in. I've never seen anyone selling a 1420mhz microwave generator with any significant power for a reasonable price. We use a 915mhz to generate plasma here, and 2450 works fine too. Both have low reflected power under a reasonable load. So you have some room to work. As for understanding E&M, why not start with Griffiths Electrodynamics textbook?