For Everyone Feeling Down...

I have to post this because somebody, somewhere, feels really down right now. This is`also for all you people not in the limelight but who wish to be. Plus, all those who fall short of their own expectations.

My thanks to "Featographie" for introducing this video to me.

The Low-Temperature Fairground

Well, There are not enough comments over here to keep this thing going, but I love my physics so much, I will do so. However, here's a point which piques the curiosity....

Superconductivity. Superfluidity.

What are they?

It happens at low temperatures. Low temperatures.

Very low temperatures.

Ok, without the details, here is what you see...

1. Substances conduct current for years without a power source.

2. Liquids appear emptier than empty space.

3. Liquids fall out of their own containers by themselves.

Helium is called a superfluid and has been well-studied. It seems to look like a combination of two different Heliums (maybe "Helia"??). Called Type 1 and Type 2. It exhibits superfluidity according to how near it is the Lambda point at 2.17 K. Only when it reaches 2.17 K does it become truly superfluid.

These are number 2 and 3 above. Technical term for No2 in "viscosity" - that is a word that means how hard it is to move a hand through the fluid. For instance, it is more difficult to move your hand through crude oil than through water, and more difficult to move your hand through water than any gas (gases and liquids are both called fluids in physics). As for the liquid Helium, is is easier to move anything through it than a gas, or even empty space. It feels like it is not there. It has zero viscosity.

No 3: A strange property of zero viscosity is that there is no resistance to the flow. The molecular movement inside the Helium is enough to drive it up the sides of any container ( from which it has no friction at all ), climb over the rim, and run down and drip from the lowest point.

As for metals, which is No 1 above, or more specifically, ceramics, the behave like there is nothing to stop the electricity flowing.

Ceramics are studied because their "lamba point" is much higher than 2.17 K. In fact, and this is not my field, but ceramics were close to having a lambda point at close to 79 K. This is significant because this is the boiling point of Nitrogen, and Nitrogen is much more common than Helium (Nitrogen is 78% of our atmosphere, Helium can only be gotten from rocks), and so is much, much cheaper.

However, for our coils, they have to copper, as here we have the conservation of energy again, as the advantage gained in the higher temperature superconductivity, is offset by the fact that ceramics are not good conductors.

Copper has lots of free electrons in it, Ceramics do not, and we can get a bigger non-resistive current if we are prepared to pay for the more expensive Helium.

Upshot is,

Copper: bigger current, lower temperature for switching superconductivity on, therefore more expensive Helium is needed.

The Ceramics: smaller current, but higher temperature for superconductivity switch on, therefore cheaper because maybe only Nitrogen needed.

The LHC needs copper to power the large magnets because the particles go so fast we need the magnets to be far more powerful because they have to turn the now heavier particles because of special relativity ( lol too many "because's )

Swings and roundabouts with a vengeance.

The "Discovery" of Absolute Zero

This is a chart to show what happens when we chill out. More specifically, what happens to a gas.

Everyone knows what happens when it gets cold.....things SHRINK (men would know more about this).

It has to do with vibration (don't get excited, girls).

Heat = energy and the less heat an object has, the less it's vibration.

So the size decreases.

If you are talking gas (Ethel Merman go home) then for the same amount of gas, if you cool it, the container you need to keep it in will have to be smaller.

There was once a guy named Charles, who figured this out, but he did not stop there.
He said to himself, what if, the gas did not go to a liquid, bur instead stayed as a gas? He called it an "Ideal Gas".

The buckshot (whoops, Upshot) was that he continued the picture right back to zero volume ( as per the picture) and he found out that no matter WHAT gas was used, they all ended up at zero volume at EXACTLY the same "temperature".

It was from then on called "Absolute Zero". and the number is 273.16 degrees Celsius below the freezing point of water.

Nothing has ever been cooled further since.

This whole issue is couched in quantum mechanics, although at the time, it wasn't even thought of. The reason why quantum mechanics comes into it is down to Heisenberg again - the Uncertainly Principle. If something stops moving, then you can say where it is (Trivial, I know, but hang on). This is completely forbidden by quantum mechanics. Moving targets are a must!

So stuff need to keep moving. and if you are at absolute zero, you stop. Therefore, you cannot get there (thermodynamics again).

Physics is wonderful because basically all the stuff around us is related to everything else. It's only when you study really hard do you get to know (and wonder at) how it all fits together.

This is the be-all and end-all of why the subject is so dear to me. You can call me a "bore" but at least I know the answers to the questions we have all asked our parents as kids.

Water, or di-hydrogen oxide, is the strangest of all, and blatantly refuses to conform....!

Why does ice float?

The Great Gig in the Sky

Richard (Rick) Wright died today aged 65.

One of the founder memebers of Pink Floyd, the quintessential English progressive rock band.

He was the drummer and keyboardist.

Their most famous album being "Dark Side of the Moon" (1973), and quite out of the blue, Rick wrote this.

Or did he? There is a rumor that Clare Torry improvised the whole thing and they published it anyway.

Either way, the only piece ever to come close has been Mike Oldfield's "The Inner Child" from "Tubular Bells III".

Comments are welcome.

Why the LHC is so large

Here is a picture of how mass incerases with speed, along with the formula.....

m-zero is the normal mass without moving
m is the mass when it is moving at speed v
c is the speed of light = 299,792,458.00 meters per second
















....and here are the actual numbers.....


1. Rel Speed of Proton = 0.5000000000

Speed of Proton = 149,896,229.0000000000

SQRT(1 - (rel)**2) = 0.8660254038

gamma = 1.1547005384



2. Rel Speed of Proton = 0.9900000000

Speed of Proton = 296,794,533.42

SQRT(1 - (rel)**2) = 0.1410673598

gamma = 7.0888120501



3. Rel Speed of Proton = 0.9999000000

Speed of Proton = 299,762,478.7542

SQRT(1 - (rel)**2) = 0.0141417821

gamma = 70.7124459519



4. Rel Speed of Proton = 0.9999999900

Speed of Proton = 299,792,455.0020750000

SQRT(1 - (rel)**2) = 0.0001414214

gamma = 7,071.0678529787


The proton/anti-proton speed and the speed of light are in meters per second, the relative speed of the proton (rel = proton speed /light speed)is with respect to the speed of light eg 0.99 is 99%. SQRT(1 - (rel)**2) is the denominator in the equation in the diagram, and Gamma is the number of times the mass increases. It can be seen that even at half the speed of light, there is a definite measurable mass increase.

This mass increase is real, not an illusion, and at number 4, which is where the LHC will be next spring, we will have a proton weighing 7,071*936 units smashing into and anti-proton weighing 7,071*936 units, giving us a total of about 13 million units of pure energy. That's 13,000 GeV. When the heaviest particle ever created is compared to this at 90 GeV, an idea can be envisaged as to just how big an experiment this is. However, panic should not ensue, as the size of the units are irrelevant, you only need to notice how much more energy we have now than before, and it is an awful lot.

Suffice it to say, in order to bend the path of a proton that "weighs" 7,000 times more than normal, a bigger curve is needed, and I back-refer to the speed-boat/Ocean Oil Tanker example given earlier.

The next few months are going to be very exciting indeed.

Explanation of a Black Hole

There has been lots of bad press about the LHC concerning the possibility of producing "mini black holes that could swallow up the Earth".

Call this post the "anti-Newspaper" if you like.

Ok, so, Black Holes - what are they?

Keeping it simple, here we go.

Stars. Stars are simply large bundles of stuff (mainly hydrogen or protons) that are powered by nuclear reactions, the same kind as in the atom bomb. The reason they do not explode like an atom bomb is that there is so much stuff there, that gravity keeps it all in a ball and contains the millions of atom bombs going off every second.

It is a matter of balance between outward nuclear explosions, and the pressure inwards from the gravity.

That's for a normal star.

However they do not last forever, and there will come a point when there is no hydrogen left to explode. The star shrinks until gravity raises the inside temperature to be hot enough to explode the next element, Helium. When that is finished, it shrinks more, and burns even heavier elements.

Even this can't last forever, and there comes a point when it can no longer make any atom bombs at all.

It gives up at this point, and IMplodes, but the implosion goes right through the centre and what is seen is an EXplosion outwards. We call this a Nova.

What is left is a lot of stuff getting thrown out into space, leaving a small, dense stellar core the size of a small planet. This is called a white dwarf, and will cool into a red, then brown, then black dwarf. Gravity is stopped by outward atomic pressure.

That is for a normal star.

If the star is just a tad bigger to begin with, there is too much stuff in it to make a dwarf star, and the protons add electrons to themselves and all become neutrons, and the star shrinks to a smaller size. Then the IMplosion again, but what is left this time is a Neutron Star, exactly like an atomic nucleus, but the size of a city. Gravity is stopped by outward neutron pressure.

That is for a slightly larger than normal star.

If the star is bigger than about 2.3 times the size of our sun, nothing can stop the shrinking and gravity completely takes over.

To everyone outside, the star is crushed out of existence and becomes a Black Hole.

The size of these black holes depends on the original star, so at 2.3 times bigger than the sun, the black hole would be roughly the size of a football field.

Clearly, most stars are far bigger than the sun, which would mean that their black holes could be as big as a planet. Hovever, this would require a billion billion billion billion tonnes of mass to create.

All due to gravity.

The upshot is that a black hole is formed from compression, of any kind, but we only know about how gravity does it, However, it has been conjectured that during the Big Bang, pressures were so great that the possibility of black hole formation at that time is entirely feasible, bearing in mind that all the stuff of the universe was there at the time to create them.

The fears that the LHC can form mini-black holes are completely groundless because a) the pressure there is about a trillion trillion times less than needed, b) there is simply not enough stuff to make one even if the pressure was available, and c) in order to "swallow the earth" the created black hole would have to be at least as big as the earth.

Ever tried pushing a water melon through the eye of a needle?

Size IS Important

The Last Post may have been just that for some. Here is an even simpler explanation of what it is all about:

It's all down to E = mc2 (Multiply the speed of light by itself, multiply by the mass of a particle, and that is how much energy (in the form of electromagnetic waves, ie light) is available to carry on.

Matter plus anti-matter = energy.

However, If you have a proton (936 units) and touch it with an anti proton(936 units) all the energy you will get will be 2*936 = 1872 units.

So we speed them up a little, so that when they eventually touch, not only do we have 1872 units of energy, we also have the energy of their motion to add as well (kinetic energy) from the acceleration produced by the power invested in the magnets. Einstein helps again, as the faster they go the heavier they get, so much so that we can't deal with 2*936 anymore, but 2* ((10 or 20)*936) units of energy.

This is a lot of energy confined to a very small space. In fact, too, much, and "snaps" new particles into being using the E=mc2 in reverse this time. What comes out depends on conditions, but sometimes a completely new and really "heavy" particle is created.

As the machines get larger (they get larger because the particles get so heavy, we need more space to turn them, just as in real life, it is harder to turn an ocean tanker than a speedboat, so size IS important!), more energy is available at collision time.

So the essence of what we try to do is take known particles, speed them up, use E=mc2, smash them together and look at the bits. The bits are different when there is more energy available to create the heaviest ones.

The effect is rather bizarre if you think of it in everyday terms......Two unmanned sports cars at great speed collide head-on in a tunnel, and from one end emerges not bits of sports cars, but a slow and fully functional 18-wheeled articulated lorry, which very quickly explodes into several dozen kids tricycles of varying sizes, which scatter in all directions like frightened rabbits.

And who said travel wasn't fun?

The Big Bang at the LHC

Well, we are on our way.

Both beams of particles have been sent their wending ways, protons clockwise, anti-protons anti-clockwise (how appropriate!).

Today was just a fire-up test of the big machine, to prove that we could actually shine particles through the 1000+ steering magnets(dipoles) and the countless other focussing magnets (quadrupoles).

The proton stage this morning was actually done in half the time expected, with a corresponding timescale for the anti-protons.

We got them both up to 99.99% the speed of light. The goal, when all is working optimally, is 99.9999999 % the speed of light. That won't be until next March or April. That is also the time when the Black Hole Doosmdayers will emerge from the woodwork again

For myself, it was wonderful to see the actual beam on the screens in the control room of CMS. This project is older than I am !

Now that we know we can use it, tweaks will be made to refine the beam solid angle and it's centrality (which by today's results was pretty central anyway).

Here's the overview of the whole shebang. Protons one way, anti-protons the other way. This works because they are of opposite charge, but obey the same rule we learned in school : Fleming's Left Hand Rule.

The steering magnets do just that, they turn the beam in a circle (actually, the particles only describe arcs of circles whist under the influence of the magnets. Between the magnets, they run straight lines)

The reason why so much power is needed and why it is being shut down for Christmas is due to Einstein.

He said, the faster a particle goes, the heavier it gets. Newton said heavier things need bigger forces on them to change their trajectories (Newton's 1st Law), so we have to up the power of the magnets many times to cope with the increased mass.

The only way to do this and not blow a fuse is to have the magnets surrounded by superconducting coils. Superconductivity happens at very low temperatures, and what happens is so mysterious it could well be science fiction. An electrical current in a wire at those temperatures suffers no electrical resistance at all, and therefore no power loss.

This is what happens, our coils are superconducting, and once the current giving rise to the magnetic field is established, we can turn off the power. Of course, you don't get something for nothing, because now we have to provide power into maintaining the very cold temperature (colder than deep space).

That's how we steer the particles. To make the beam narrower and therefore more focussed, we use quadrupole magnets.

Recall that schoolboy magnets have two poles, north and south (they are the dipoles above). Quadrupoles have two norths and two south poles, and the magnetic field lines, unlike the dipoles which are straight, are curved, and they flatten the beam's solid angle into a thinner beam.

Dipoles steer, quadrupoles focus ( you can have octupoles and hexadecapoles with 8 and 16 poles respectively as well, but NOT decapoles (10 poles) or duodecapoles (12 poles))

So assuming the LHC is now fully operational in the Spring, what then? Well, we get the opposing beams to cross at 5 points around the ring, looking for where proton meets anti-proton, and using E = mc2, a maasive amount of energy is available to create new particles from the electromagnetic waves created. The energy available is so great, it had been labelled "The Big Bang" experiment.

And what is it we are looking for,exactly, the cry goes out?

Ever since physics began a very basic question has been asked. Exactly what determines each particles' mass (=weight). More specifically, why is a proton 936 units, a neutron 939 units, and an electron 0.511 of the same units? We know how to perform calculations with these numbers, but where do the actual numbers come FROM?

Nobody actually knows. However, Peter Higgs, a British Scientist proposed a gauge field (like an electromagnetic and gravity field) called the Higgs Field, which all particles move through and acquire mass from . All gauge fields have an associated carrier particle (electromagnetism has the photon, the strong force has the gluon, gravity has the graviton, and the weak force has the W and Z0, all of them Bosons (ie "spin" is integral))

The Higgs Boson would be the carrier of the Higgs field, and is so heavy that no accelerator has been powerful enough to produce one, until perhaps now.

THIS is the Holy Grail of Physics.

It is exciting because, if we DO find it (and we won't see it directly, it dies very quickly), we will know a lot more about physics, and if we DON'T find it , that means we do not quite understand what is happening yet, and a radical re-think will be in order.

Personally, I agree with Stephen Hawking, in that I am willing to bet it will not be found.

Music to My Ears

First, in the early eighties, we had the Walkman, a personal, portable, cassette tape player.

After the onset of audio CD's in 1985, Sony brought out the Discman, a personal, portable CD player.

These were all the rage until in recent years, the mp3 player came along.

As as a traveller, I observed a drawback to the mp3 players.

When you loaded your music onto, say 2Gb of mp3 player, you could not change it without a computer, AND, if it was fairly full, you had to scroll through all preceding tracks to get to the one you wanted .... a bit like what you had to do with the cassette tapes.

At least, with the Discman, you could change discs.

In the photoworld, the card reader was invented, and it looked like THIS:





















The little black thing was interchangable flash memory and it meant that you could have more than one and interchange those photos with all the other memory cards you had.

Here's an mp3 player:





Notice, please, the similarity.

Somebody else somewhere is going to have this thought that I have recently had:

Whay not make an mp3 player with a built in card reader? It would still be an mp3 player, but have the flexibility of a CD player.

This way, you could carry your unit around, with memory cards that were "Pink Floyd", "Josh Groban", Iron Maiden", and listen to them by interchanging them, rather than scroll through the 2Gb looking for them.

I reckon this will happen before the end of 2009, and it would be music to my ears.

The Largest Telescope On Earth

This is it - September 10th. Switch on time for the "largest telescope" on the planet.

The LHC - Large hadron Collider - is a particle accelerator the like of which has never been seen before.

It is a circular tube 27km in circumference, so large that when you look down it, it appears straight.

Although particle physics is one level above me, I still understand most of what happens there.

The whole tube is a vacuum, and we will send protons around it at speeds never dreamed of before. In the other direction, we send antiprotons. Antiprotons have everything in them reversed,except mass. This means they are negatively charged, and because they are the same mass, the same magnets can be used to turn them.

The current in the magnetic coils are so large and energy draining they have to be cooled to 1.9 Deg K, that is -271.1 deg C to make the current superconducting. Superconductivity only happens at these cold temperatures and the upshot is that the electrical resistance of the wires disappears, so the power can be switched off.

At various points on the circuit, the two beams of particles cross and BANG.

Particle plus antiparticle means they both disappear into electromagnetic waves.

But these waves have so much energy, they don't last for long and SNAP, just like putting enough stretching energy into an elastic band will make it SNAP.

What comes out of the SNAP is a plethora of new particles and antiparticles, some of which we may not have seen yet.

What is worrying is that a gamut of people claim that creating a mini Big Bang (very mini compared to infinite energy) will produce strange things that will annihilate the Earth as well. Mini black holes are feared also (the same size of a proton), but they would not last long either.

September 10th will be a day long remembered, and I WILL BE THERE!!!!

Geneva expects.

Incidentally, the telescope analogy is valid because normal telecopes optically see small things (distant stars) and this "telescope" also "sees" small things with the huge ATLAS detector.

To those people worried about mini black holes the size of proton, this is just silly. Why? To create a black hole that small would still require the mass of a good-sized mountain, but the total mass of the particles in the tube is less than 1 gram.