Severian

It doesn't matter where it comes from; beta radiation is made of electrons and a gamma radiation is made of photons.

I take issue with the phrase "the Beta particle is the type of radiation closest to an electron". A beta particle is an electron! Other than that is seems right though. It is a bit low energy inspired, so some of the statements are really only true in certain contexts, but these contexts are the ones in which you would normally be considering beta radiation, so that is fine. (For example the associated photon can be emitted together with the electron (the gamma particle he mentions) need not be soft if the source produces high energy electrons.)

Well, if this thread isn't spam, I don't know what is!

I suspect that the people who we call geniuses are really only 'different' from other people. Their brains are wired slightly differently and so they see things that 'normal' people might not see, but they also don't see things which seem fairly obvious to 'normal folks. Einstein was a classic example of this - he appeared rather ill at ease with a lot of the more normal activities. I suspect that if we had a planet full of Einsteins, and dropped one of our average SFN members into the mix, they would regard him/her as a 'genious' too.

In fact, only two of them do: the photon and the gluon (and the graviton if you want to count it). The other force carriers, the W+, W- and Z bosons have large masses, so they do not travel at c.

The problem is that you are not realizing that the velocity of the train is a frame dependent measurement. When you measure the velocity, the answer you get depends on the train you are in. So if I am in train number 345 and I measure the speed of train 346, I will find it is travelling at 0.99c relative to me. If I am on the ground and measure the speed of train 346 I will find it is travelling at 0.9999999c (or whatever the maths gives). Since the addition of the speeds is not linear when you get near c, none of the trains will ever be travelling at c or faster compared to me. So you can go as far as you want with the train embedding, and you will never reach a limit.

Let's face it. Democracy is a dreadful way of running a country. Look at the average voter and ask yourself if they are qualified to choose decide who will form the best government. Of course not! The only form of government worse than democracy are all the other forms of government.

Since Martin is advertising conferences on his favourite topics, I thought I would do the same. Next week is the international conference on supersymmetry, SUSY 2005. Unfortunately there are no public talks and no video conferencing (unlike the flash string theorists) but slides of talks should become available after they are given.

At the simplest level, time and space are merely labels for categorizing events. So, if you imagine the universe as being a collection of events, then where and when it happened is just a categorization of that event, like the index of an array in computing (albeit a continuous index). Then there is an additional concept of space-time distance, which provides a definition (via a metric) of the distance between two events according to some rule made up from these space-time indices. For example, the traditional 3d distance squared you are used to in the real world is (x1-x2)^2+(y1-y2)^2+(z1-z2)^2. In a 4d Minkowski flat space-time (these words just specify the definition of the rule) the distance squared is (t1-t2)^2-(x1-x2)^2-(y1-y2)^2-(z1-z2)^2. GR tells us that these rules can be altered by objects.

I think I would dispute the five.

I seemed perfectly clear to me. Abortion is illegal in Portugal, and a referendum in 1998 to change that situation was held in 1998 and defeated (i.e the people were asked in a vote if they thought abortion should be legalised and they said 'no'). The parliament (which is democratic, and therefore votes on things itself before making decisions) has decided to hold another referendum on the same issue this year. Rampant paranoia from Pangloss I think....

No, I was serious! Cosmology is entering a new phase. They have now done the basic stuff and will, on the next round of things, need to introduce some precision which means calculating loops. I reckon there will be a lot of cosmology papers with loops soon, although they may not be LQG. Actually, the 'quantum' might scupper my 107 since I am relying on them not all being LQG, but if you look at your links there are quite a few in there which are not LQG.

I will admit that I may have the wrong end of the stick' date=' since I am not very sure what Hawking has said about this. I was assuming that he was talking about the metric shift (that is what people normally mean when they say 'imaginary time') but of course it could be something entirely different. Could you please provide a link to the source? You also contradict yourself: Which is it?

Martin has gone poll crazy! Put me down for a cool 107...

Imaginary time is just an artifact to make the metric Euclidean rather than Minkowski. It has no measurable consequences, but is just a different way of presenting the theory. It is completely equivalent to 'real' time, and neither version is 'right' or 'wrong'. EL: What are you smoking?

My guess is 4

I reckon it was the French.

But why do you say 'mass cannot'? I suspect you are simply extrapolating GR, and naive quantum gravity, to very very high energies. I am not convinced this is valid. Though if it is, you are correct, there would be a problem. Gravity would become so strong that the energy density would be large enough to 'foam' space-time, creating lots of little black holes, long before we reached the singularity.

Thought not. I personally don't find an oscillating universe very appealing.

They do move! That is the whole basis of GR - the energy-momentum of matter distorts the space-time metric. Or are you meaning something else?

It make sense from a mathematical perspective. All that distinguishes time from space in the theory is the signature of the metric. You could add another dimension which has a the same sign in the metric as normal time and it would officially be an extra time dimension. I am not sure how you would interpret the results though.

If something can be proven then belief is not required. That is the problem with your criterion - belief and proof are mutually exclusive, and since sceince is based on proof it cannot be a belief.

Science can also be a fruit if I tell you what my definition of 'fruit' is.