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Thanks for that helpful blog post Philg!

Field medalist Tim Gowers' "Very Short Introduction to Mathematics" is good (if very short ;-) ). Actually, some of the other books in the "Very Short Introduction" series might be worth a look as well. http://www.amazon.co.uk/Mathematics-Very-Short-Introduction-Introductions/dp/0192853619 Not a tex...

Thanks for posting this!

LHC Operations Status Report - a nice summary of the state of play
http://indico.cern.ch/conferenceDisplay.py?confId=95508

(Apologies if this has been posted already)

PhilG, thanks for your long reply! Really sorry I have not responded yet - I hope to have the time to do so properly soon.

I am not sure why you included the length of the tunnel and the length of a bunch in your calculation? Also, the number of protons enters the luminosity quadratically (they must hit each other, not a brick wall!). There is also a geometric factor due to the beams crossing at an angle, rather than he...

@PhilG: I hesitate to say this because you are not quoting anyone or anything specific - but I think you are rather quick to call "nonsense" when referring to statements taken completely out of context. Quite often what happens is that a particular mathematical fact is expressed in words, and that c...

Photons have an energy proportional to their frequency. By E=mc^2, this means they have a mass (though no rest mass - so they cannot be at rest). Therefore, they source a gravitational field and bend spacetime, just like any other mass. However, this does not explain the apparent violation of energy...

why they don't collect a given number of events... Ultimately this is of course just a convention, but I think it is because one is usually interested in the number of collision events *of a particular type* (e.g., Beauty production). A calculation on the theory side will traditionally produce the ...

That's great news - Congratulations!

Excellent

So, what energy is released into the block in total ? the 3.5TeV?

Yes! No energy is ever lost... it all has to go somewhere...

I think I see your misunderstanding. Of course if you send a 3.5 TeV proton into a beam dump, that energy will not disappear - it will end up in the beam dump, making the beam dump hotter. It will end up there like the previous 2 posts describe - a cascade of collisions and scatterings, a bit like a...

The details of the beam dump are not really important for Xymox' question, because for the comparison with head-on collisions only the first collision of each proton matters. The reason his intuition is failing him is because the beam is moving so close to the speed of light, so relativistic effects...

Virtual particles FAQ http://math.ucr.edu/home/baez/physics/Q ... icles.html

@chriwi While it's fun to speculate, and I'm not sure I understand your idea, ultimately we'll find out when some quantum gravity theory is experimentally proven... BUT Lorentz invariance (which is experimentally very well established) does rule out a lot of things. @ansgar: I see what you're gettin...