imatfaal

But a science built upon solely philosophical principles and logic, but without maths and experimentation is wasteful and sterile. Whilst some beautiful extrapolations and theories can emerge they are a dead end - because being logical consistent and philosophically pleasing does not imply they will even approximate reality. You might say that some of the theories may be the breakthrough that mathematically-constrained science was unable to make - but again this fails; science without maths/experimentation has no way of testing itself apart form self-consistency. Whilst a non-rigorous approach may generate a delicate spectrum of elegant hypotheses; to test these we need to move back to the lumpen reality of maths and measurement. Conversely, the great breakthroughs of the twentieth century came from believing in the inviolability of the maths and experimentation and rejecting the dogma and restrictions of the more philosophical view (ie rejection of absolute space and time to create a system of transformations/IRs in which c is constant). I fail to see how the concept of conservation of energy (and your other examples) can really help to make progress without maths - sure it can produce an ephemeral surface veneer of knowledge - but without the knowledge of the intricacies it comprises this is nothing more than a pleasing aphorism that allows no progress.

Gravity overcome mass? Not sure what that means. On the big crunch issue - I think the balance of opinion is that galaxies have escape velocity and will thus continue to spread out, rather than slow and begin to contract. It is all to do with the average mass/energy density, if the density is high enough then the speed with which galaxies are moving apart will not be enough and sooner or later they will fall back together, if the density is below that critical figure then the galaxies have enough speed to escape forever. This means we need to know the relative velocity with great precision and the amount of mass/energy in the universe similarly. Around 15 years the sums lead scientists to the conclusion that the expansion was not only fast enough overcome gravitational attraction but was actually accelerating - this is the dark energy question. the fact that we really don't know the rationale of dark energy means that nothing can be really ruled out until we do understand that.

Can I make sure I understand the problem in its most basic form; is the question whether a photon and a graviton emitted by an object will follow the same geodesic path through space time? And if so; what causes the curvature upon which the graviton follows its geodesic? Isn't this dangerously close to attempting to merge general relativity and quantum field theory? - ie getting pretty difficult

I have just looked through Dave's great tutorial on Latex and wonder if the original post could be altered in one small way to avoid confusion. I noticed this from Michel's point on the Stonehenge Mathematics. Michel had, quite reasonably, looked at the Tutorial and I guess this line specifically He had wanted to get the symbol for pi. If you find an equation on the tutorial with pi - click and look at the code is appears as follows [ math]int_{-infty}^{infty} e^{-x^2} = sqrt{pi}[ /math] It has stripped out the backslashes if you then try to put what the code shows you get [ math] =sqrt{pi} [ /math] gives [math] =sqrt{pi} [/math] rather than [ math] =\sqrt{\pi} [ /math] gives [math] =\sqrt{\pi} [/math] It would be useful to add a little line explaining that symbols need a preceding backslash that has been stripped out in the examples

I would go along with Mooey that this is a good example of why we should stick to metric units; I would also agree with Mooey's answer. Although I would question giving to two dp when you are using 32 f/s/s - my estimate of the errors inherent mean that you cannot be sure of even the unit figure let alone decimals. The prof seems to have made a clear mistake by failing to square the velocity .

No it very much makes sense. the relative velocity between galaxies is proportional to their distance apart - close galaxies move away from each other slowly, distant galaxies race apart. Lose the idea that the galaxies are all moving at same speed - it will not help. The background and space itself is expanding - imagine an oldfashioned cartesian grid on which the universe is set, every second (in each axis) add one more unit for every 10^17 units . the playing surface has got bigger, the pieces are further apart, but none of the pieces have really moved relative to the surface. There are some galaxies we can see (obviously) and some that we will never see

I dunno about T-Rex being faster than an elephant - they move pretty quickly when they want to and one of the articles referenced by the earlier Nature article on TRex mass was called Tyrannosaurus was not a runner From the abstract However, models show that in order to run quickly, an adultTyrannosaurus would have needed an unreasonably large mass of extensor muscle, even with generous assumptions. Therefore, it is doubtful that Tyrannosaurus and other huge dinosaurs (6,000 kg) were capable runners or could reach high speeds. From the article Tyrannosaurus shows the most extreme cursorial (that is, locomotion-related) specializations of larger theropods, but even it was probably a slow runner, at best.

Where on earth is it a strict liability offence to have an erection in public? Is it a dead letter that has been on the statute books for centuries?

[math] \pi [/math] \pi Pi doesn't need curly brackets - just a backslash. Like the way of measuring area.

Did anyone order salad?

If you need references there are 88 at the bottom of the dark matter pages alone. If those pages are too simple you are going to be more specific on your question.

Why not - surely growing at less than the speed of light is fairly acceptable, No? Cannot see this logical connexion with your second sentence. Are you asking about inflation or expansion? Inflation is only recognisable by archaeological methods and agreement with theory - inflation was a vanishingly small fraction of a second after the bigbang; we can observe directly nothing before about 380000 years after big bang. After inflation during reheating the energy of expanding space was converted to radiation/standard particles

spyman put together a nice post with brief entries on dark matter, dark energy and anti-matter with links to more info it's here http://www.scienceforums.net/topic/56901-dark-matter-anti-matter/ at post 10

it's all down to the fact that socks without holes are in effect an M2 brane - it is all part of Horava and Witten’s Heterotic M theory and the notion of “upstairs” and "downstairs" solutions http://deposit.ddb.de/cgi-bin/dokserv?idn=960253386&dok_var=d1&dok_ext=pdf&filename=960253386.pdf http://arxiv.org/PS_cache/hep-th/pdf/9711/9711014v1.pdf the answer is quite clear - we need to encompass both forms of solution - the socks are both upstairs and downstairs; there is always a positive finite possibility that if the left sock is upstairs then the right is downstairs.

Michel - from a quick look at the literature I think your reasoning is good and not circular. the mass of T-Rex is estimated from far more than the print size; among those factors considered bone mass, muscle mass (estimated from tendon attachments on bone), toothsize (from marks on prey) and even poo-size (A king-sized theropod coprolite. Nature 393, 680−68)

Not sure about the perspectives bit - but otherwise yes. there are parts of the universe that are moving away from other parts such that the distance is growing faster than light could cross the gap. The relative velocity between galaxies increases with distance - unless you put a bound on the maximum distance then at some distance apart the relative velocity seems higher than the speed of light. Bear in mind however that nothing is moving through space with the speed of light; in simplistic terms more space is being added between them. inflation and expansion are not the same - inflation was rapid extreme and was at a period of the universe we can probe only through echoes and archaeology, expansion is now.

6k +/-1 is just no back up at all to your theory. It is easily rationalised and doesnt tell us anything; 6k must be even, you cannot say much about 6k -1, 6k -2 again even, 6k-3 must be divisible by 3, 6k -4 must be even, 6k -5 = 6(k-1) +1. That accounts for all numbers the only ones not divisible by 2 or 3 are 6k+1 and 6k-1 Clearly the number between twin primes must be divisible by 6, ( ie one of the primes is 6k+1 and the other is 6k-1)- i it must be an even between two odds - divisible by two ii any three consecutive numbers one must be divisible by three, obviously neither of the primes can be divisible by 3 therefore the middle one must be iii any number divisible by 3 and 2 is divisible by 6 But this still doesn't help you. DocRock has provided a link to the Wikipedia page which briefly outlines prime number theorem, and a reference for further reading. And a simple numerical test shows that your prediction is miles out

Athena - I am not a great fan of mysticism within mathematics, but I can see where the attraction comes from You might want to look into the great German Mathematician Gottfried Leibniz and his work on the binary number system in which he looked at (in some accounts was inspired by) I-ching and the work of Chinese Mathematician Shao Yung. Whilst I can see the 64 link with the codons of DNA and i-ching - the 64s are different 64s if that makes sense. I-ching is binary ie 6 bars which can be in two forms (2^6=64) whereas DNA codon is 3 bases with 4 variation (4^3). I just see those as different - but that may just be me.

Q(the winged serpent) - if you refuse to read the articles that prove mathematically that you are incorrect; could you explain why something that has a frequency of 1 in 6 in your theory doesn't even come to approximating that for the first 10000 primes. If you are even close to being right then the 10,000th prime should be around 60,000; well it is the work of two minutes to find that the 10,000th prime is 104,729. the prime number theorem linked to above is much closer than you and it gets better as the numbers get bigger. As another bigger example the 50millionth prime (again a minute on the internet) is at 982,451,653 - your theory would predict is around 300,000,000, the prime number theorem which is getting into its stride would estimate that you would get 50,000,000 million primes around 1,038,029,502. Regardless of the charts and your DFT and banding, in simple terms frequency can be looked at by how many in a given large spread - and your ideas do not hold water.

This is fairly standard way of displaying the 64 3bit codons of DNA - obviously it is a matrix with three dimensions but for readability is drawn in two The terms like Phe - are shortened names of the amino acids Phe - is Phenyl Alanine , Leu is Leucine etc. Table copied from here http://www.nature.com/scitable/topicpage/nucleic-acids-to-amino-acids-dna-specifies-935

for a fun pp-sci read that breaks new ground very gently try Chad Orzel's How to Teach (Quantum) Physics to your Dog.

As a system it is open to manipulation, enforces cliques, and equates being in the majority with being correct; all of which are dangerous. But as a rating process it is objective, systematic and relies on the actions of scientific community rather than arbitrary judgment. Just as democracy is a terrible system and a benevolent dictatorship is preferable so it is in this situation. An honest panel of the great and the good wisely distributing honours, promotions, grants and funding without fear or favour on the sole basis of academic merit would be marvellous; but we know this could never happen in the real world. So we accept a halfway house, a muddy compromise with both objective and subjective measures that satisfies no one, yet is the best of a bad bunch.

Interesting that we have come so far that Anglo-Saxon is used as an antonym for German.

there is also a sort of evolutionary selection going on as well - the bands that survive 30/40/50 years are the ones that deserve to. Comparing the Who or the Stones to any band now is just unfair - these are the survivors and only time can tell who the survivors will be from the 2010s. From a quick survey of my itunes library about a quarter of just of two thousand albums are from before I was born - and I would consider myself someone who prefers old music. I reckon Kings of Leon will survive, White Stripes, people will talk about and listen to NWA Dr Dre etc or similarly Joy Division for many years because of their historical importance, and hopefully every PopStar/Britains Got Talent/X Factor (Delete as applicable) winner will disappear without trace as soon as pssible CaptP is dead right in saying that the capacity to hold music has grown immeasureably - 2156 albums in the time of vinyl would be several rooms worth; they now sit on a device about the size of a text book (at home, at work and on portable HDD).

Lemur There is superfluidity - which is a strange state of matter that seems to allow the substance to behave unusually (it has zero viscosity and complete thermal conductivity) You can read up here http://en.wikipedia.org/wiki/Superfluid and here http://hyperphysics.phy-astr.gsu.edu/hbase/lhel.html Nice video In a way this can be called frictionless - the atoms (or now molecules) do not hinder the progress of their fellows - this is what leads to the zero viscosity. I don't know if a foreign body would be frictionless - although my feeling is not