5614

A bit over 48 hours.

It's when there's a change in the Matrix! I once went to a big party in a house I've never been to before and there was a massive temporary marquee and I went into it and it was just like, I'd been there before. But yet I'd never been to this house, never seen this marquee or anything. It was weird. And it wasn't just like a past recolection, I vivdly remembered it from somewhere. Weird.

Swansont touched on an interesting point. The only way you can get a wire where R=0 is with a superconductor. However if you apply a magnetic field to a superconductor it will lose it superconducting properties... so how can you apply a magnetic field to a wire with R=0?

So I downloaded the file and scanned the .exe (the .idx file is fine) but the .exe contains a Trojan Horse named (by Avast) Win32:Trojano-CE So yes it is effectively a virus, although technically it's a trojan. I did a quick google search and didn't come up with much. I suggest you download Avast Home (it's free) and schedule a boot time scan (after updating it) because I know that Avast will detect this trojan because it did for me so it will for you (remember to update though).

My point is that if you have a photon with frequency 'f' and you want to calculate it's energy then if you use h you get one value and if you use hbar you get a different answer. That photon has a specific energy, it cannot be one of two depending on how you feel. Only h gets you the right answer in that equation, using hbar yields an incorrect answer.

Sounds like you want to go into Physics, more specifically particle physics (for the anti matter and/or gravity) but maybe something more like aerospace or aeronautical engineering for the space vehicle.

I've also been told that at higher level maths people use log to denote ln. Apparently at that level who needs base 10 when you have base e?

It's 12hrs 34mins 56sec twice a day every day!

Oh yeah. Google Linux: http://www.google.com/linux Google Mac: http://www.google.com/mac.html

[math]E = mc^2[/math] is not wrong, but it can only be applied in certain circumstances. For example it cannot be used for a photon. If negative mass existed (it doesn't, but say it did) then this would just be another case when you can't use the simplified version of Einstein's equation, nothing wrong with that. Einstein's forumla was not [math]E = mc^2[/math]. Einstein said that [math]E^2 = (mc^2 )^2 + (pc)^2[/math] and he did realise that the powers would allow for a postive or negative answer. He did not rule out the possibility of negative energy. I don't know his thoughts on negative mass. I see what you mean it is kind of cheating. But using that method is succesful in many physics and statistics formulae. It works.

Yeah. I'd like to see you let go at exactly 22.5 degrees!

I know that [math]\hbar = \frac{h}{2 \pi } [/math] So if you said that [math]p_{photon} = h / \lambda[/math] could you say that [math]p = \hbar / \lambda[/math]? I don't think you could but if you look somewhere like here: http://scienceworld.wolfram.com/physics/PlanckTime.html then it shows both h and hbar used in the same equation. Surely only one can give the right answer. Actually, maybe they're not the same formula. One is for tp and the other for t'p.... what's the difference?

Moving a magnet up and down a wire can induce a current, spose that's kinda wireless. At the end of the day you can't really get much further than like 1cm. I spose lightning is quite long distance wireless electricity though.

Do you get on with your bro? Was he like really drunk or is it just a brotherly thing to threaten to get someone else to beat you (and your friends) up and then call the cops? "omfg" to that part! "rofl" to your bro, although I'll see if you get on with him before calling him a total idiot.

Nah, it was sex and drugs (16) last year... I'm 17 now so it's driving and only one more year of fake ID! ("need" to be 18 for pubs and such like) And thanks for all the presies! Cheers all

Err I'm not familiar with the ME OS. My Dad's computer (win98) sometimes used to crash on shutdown. We got used to it and the prob sorted itself out. When we formatted (for other reasons) it definately stopped, but I have a feeling it stopped before that, which would be strange because I didn't try and fix it! I assume you have all the ME updates? If it were a common prob then there could be a patch. How often do you get it? How often do you shutdown?

Dunno if this is old news to you guys and girls, but I just found this: http://www.google.com/microsoft.html It is Google but restricts your search results to "Microsoft-related sites". Useful for MS troubleshooting and stuff. As I just found it earlier I can't really say how good it is, but it looks like it might be useful.

RyanJ: Although if you consider [math]E^2 = (mc^2 )^2 + (pc)^2 [/math] then a negative mass would just be squared out. But I still don't think negative mass exists.

So does that mean I don't need to answer?! It's just that the particles have enough energy to overcome the force which normally makes them repel. Just like if I shot you at a concrete wall at say 0.5c you would have enough energy to get nice and close to it !

As a guess I'd say somewhere between the bottom and 45 degrees. Dunno, see what others have to say too.

That's a good answer... but I don't like it! So sure, both h and hbar are very small... but just freely interchanging between 2 different values in physics and saying they're both right and there's no real difference... they're different numbers, maybe like Newtonian motion it's hard to see when it might be wrong, but one must be right, making the other wrong. [math]h \neq \hbar[/math] so pretending that they are and that you can switch between them at leisure.... just, do you know what I mean? It just don't sound right.

Just finishing C2 then. Guessing you're not gonna have loadsa revision time in class. I think this kind of integration is just a case of applying this: [math]y = x^n[/math] [math]\int x^n \cdot dx = \frac{x^{n+1}}{n+1}[/math]

I remember reading something like what Swansont said. I agree. And just to state the obvious as far as we know negative mass does not exist.

The best I can do of imagining 3D is using a 3D graph, like the corner of a cube (like the inside corner of a shoe box or something). But the problem with the whole examle thing is that spacetime is not a flat surface or even a bunch of perpendicular flat surfaces (representing different dimensions) spacetime is everywhere. When trying to get realistic trying to imagine a solid cube of spacetime and warping that... just gets confusing. From which I can conclude that visualising 4D or even 3D spacetime is not something I'm going to spend hours over, because it just aint gonna work! What Atheist was saying is that what you're asking is effectively: "within GR, can spacetime be warped differently that it is warped within GR" by differently he is referring to antigravity. The obvious answer is no. GR says spacetime is warped in a specific way. Antigravity would violate this, or put differently antigravity would violate GR.

I don't think it would work in GR. Whilst I do not know enough maths to even guess if you think about it GR was made on the fundemental assumptions that all mass/energy etc. warps spacetime in a very specific way. Antigravity in GR would involve changing the fundemental assumption that all matter warps spacetime in specific ways dependant on the amount of matter etc. I don't think you could change something like that and still get GR to work. In fact the more I think about it the more I think that if some matter interacted with spacetime differently (e.g. has an antigravitational field) then GR would be incorrect. Making the safe assumption that GR is correct means antigravity cannot occur.