Einstein WAS right....

....Einstein was probably one of them!

(Close Encounters of the Third Kind)

In my last post on relativity, I intimated that the speed of light IS constant. By constant, this means the same for all observers.

Those smart-asses who say 'but the speed of light in glass and water is different, so it can't be constant' have entirely missed the point. "Constant" refers to all observers travelling in the same medium that light is travelling through at the time, be it water, air, or a vacuum.

Indeed a vacuum is always chosen because in all measurements of the speed of light, none is ever bigger than that measured in free space.

NOW we start. I doubt many people do not know where all this came from, but it is quite simple, and is called "The Principle of Relativity".

To make you realise what it is, perhaps a few questions would suffice.

How fast are you going right now? Most of you will say you are sitting, and are therefore not moving. A few will say " At about 100kph, I am on a train". The question really is, how fast you travelling relative to the Earth. The first group has answer 0 kph, and second group 100 kph, relative to the Earth.

But how fast is the Earth moving? Well, relative to the Sun, about 30,000 kph, as the Earth goes around it.

How fast is the sun moving? Well, relative to the galactic center, about another 250,000 kph.

We don't notice this because of a blanket surrounding us called "The Atmosphere" which travels along with the Earth, so we are only aware of travel on the Earth.

So, how fast are we really travelling? 100kph? 30,000 kph? 250,000 kph?, or their sum, 260,100 kph?

Yes, but what is the Galaxy moving relative to? The answer is the Local Group, and the point is, the process can go on for a long time to calculate real speeds.

So, how fast you are going actually means "How fast are you travelling past object X".

Simple mechanics with a little thought.

However, Einstein went further. His question was this:

" If in free space, with no 'object X's' to measure with, how fast are you travelling past that there other spacecraft? With a little more thought, you can see that the answer is not clearly cut, for you could be stationary, and the other spacecraft is moving past you. SO, who , in the end, can say which one is moving and which stationary? Indeed, BOTH spacecraft could be moving and you would never know the difference!

Next time you take the kids out for a drive, get in and ask them to hide under a blanket at the back, so they cannot see out. Next, jump up and down in your seat a little, your wife too, and the kids will be convinced you have started!

Point is, if you have nothing by which to tell you if you are moving (a tree, a bump in the road, another spacecraft), it is impossible to tell if you are or not! Ask the pioneers of sea exploration 200-300 years ago, they knew all about it.

Put succinctly, "free motion is impossible to detect" - the Principle of Relativity. This is where the word comes from - you have to be moving relative to something to tell that you ARE moving. THIS is the central tenet of Relativity.

What has the speed of light to do with this? Well, if true , there are certain consequences.

Einstein realised that the speed of light simply cannot be anything else BUT the speed of light, and that it was the same for all travellers, no matter how fast they travel. Otherwise they could work out how fast they were moving. For instance, if you are travelling towards another planet at 30,000 kph, the speed of light would be (speed of light (minus) 30,000 kph). SO you can calculate your speed. BUT the Principle of Relativity forbids this, therefore the speed of light is the same for them, as it is for us, here on Earth.

This principle has explained many things, a good example is a star going round another. Try to think what you would see if the speed of light were slowed down when the rotating star moved away, and what you would see when it was speeded up as it moved towards you. You would see the star in two places at once! This of course, does not happen, and is well explained by the constancy of the speed of light.

Another proof of the Principle of Relativity is in electromagnetism. Sometime back I was writing about the speed of light and electricity, and that it had actually been derived (logically deduced from) electricity and magnetism considerations alone. This also means it does not change.

Contrary to popular belief, light is not a barrier like sound is, it is more like a forcefield that grows stronger the nearer you get to it. Whereas sound barriers can be broken, it is physically impossible to go even as fast as light, let alone go faster.

When I say physically impossible, this is fact, because the harder you push to go faster, the energy you put in goes to increasing the mass (according to E = Mc**2), not to increasing the speed. Ask any particle physicist or nuclear scientist. BUT this is the realm of Special Relativity, and deserves another post, as does General Relativity. Both theories came about because of the simple tenet of the "Principle of Relativity".

From little acorns do mighty oak trees grow.

Harry Potter and the Order of the Phoenix

(VERY SUBJECTIVE POST!!)

Yes, here we go again.

As a dedicated fan of Harry Potter, I also await the new (and last) book "Harry Potter and the Deathly Hallows" with abated breath.

I STILL think that Sirius Black (Harry's Godfather, played by Gary Oldman) is alive. I have maintained it ever since he was apparently killed in the above episode.

I am also in love with HIM: (Harry Potter)





































AND desperately jealous of HER: (Cho Chang)

















Because she gets to do THIS:






















with him.....GRRRRR.

I can at least take solace in the fact that he seems to prefer the oriental type.

Maybe I can weave some of my own magic on HIM! Expelliamus!

Ultimate speed limit....?....Nah, Einstein is WRONG.

The speed of light has often been described as "The Ultimate Speed Limit", a 'barrier' because people have always been informed of this.

And, without knowing why, they have been imbibed with the belief that this is the actual scenario, without having been informed as to why this statement has been made public as if it is fact. Conesquently, they have likened it to the 'sound barrier', a totally different thing.

Hence the plethora of people (especially in the physics rooms) who believe that Einstein 'was wrong', because just like sound, they believe that the 'light barrier' can be breached.

Wrong or right, this is what happens: Nothing can travel faster than light, and what is more, there is no way to even approach those speeds.

Whatever people believe or led to believe, be it good-intentioned or not, the truth is that the speed of light is completely unnattainable. But how do I explain this in normal terms?

I deal in this stuff almost every day, so watch this space as to how it can (or cannot be done).

Most of the boffins in the physics rooms are completely unware that sound and light travel in a different way. In fact, light travels in a totally inexplicable way, to them at least, or it would if they had studied rudimentary wave theory.

The Conclusion of the Calculus...or is it?

Above here you can see what the Calculus can get up to given its wicked way.......

However, we haven't QUITE reached that level yet.....

So, we were up to ‘speed’. I had just finished introducing what ‘speed’ is.

‘Speed’ is the average over, well, in our case, an hour. In 1 hour, we travelled exactly 60 km. And in 30 minutes, we travelled 30 km. So, what was our speed in the last second? Why, 60kph of course. BUT this is not our speed NOW. That was just in the last second.

The measure of speed seems to depend on the time interval before we took the measurement, and, normally this is enough, for cars at least.

But for Math, and certainly Physics, we need more, we need the speed NOW. The way we do this is easy in principle. We begin to make our measurement over shorter and shorter time intervals, until the time interval is so small, the speed we measure is to all intents and purposes, the speed we are doing NOW.

In fact, it turns out there is a real easy way to calculate this NOW speed in Math. We do it with a technique called the Calculus.

Scientists use this technique all the time as 1). It is painfully easy for those used to it, and 2). There are so many ways we can use it, rather than just calculating how fast a car is travelling.

In fact, the use of Calculus is so widespread that Physics would fall apart if Newton hadn’t formulated it. Maybe that is a bit of a strong statement, but without Calculus, science would be completely lost.

Examples of the use of Calculus include speed, acceleration, angular momentum, currents in circuits, voltages, astronomy, black holes, relativity, tensors, athletics, rockets, brake fluids, air conditioning and quantum mechanics.

And those are only the ones from the top of my head (which is pretty small anyway!)

Suffice it to say, Calculus is the cornerstone of physics (OPINION!), and this reader is astonished that schools in the UK have deferred the teaching of it, even the basics, until after 18. And they STILL say exams are not easier here despite everyone getting A grades!

Maybe I will give some beautiful examples of how the Calculus is used in a later post……

Bring Her Home....

This picture has to be the most famous image of a little girl as was Shirley Temple in her heyday, at least in Europe.

It is plastered all over stores, billboards, near traffic lights, guardrails, stations, bus-stops, and has appeared in almost every newspaper and magazine from Here to Eternity.

She is of course, 4-year old Madeleine McCann.

The innocent girl was apparently abducted nearly two months ago in Portugal, on a family holiday.

There are countless yellow ribbons all over Liverpool. tied to railings, lamp-posts, or wherever they can be tied.

Everyone is waiting for her to come home.

Such a furore has been generated that a website has been started: http://www.bringmadeleinehome.com/.

The unique mark in her left eye makes her hard to miss, and yet.....no sign of her. Not even a whiff of a suspect.

Poor Madeleine. She would have had no idea of what was happening.

I wonder how many of my readers have heard of this case, and of what they think. OPINION: It is the writer's view that the girl was murdered soon after abduction, after the perp had had his way, and that the body will be found in Portugal near to where she disappeared.

I have heard of stuff like this happening in America ( exclude Korea on this count), but we don't get the coverage over in the UK that THIS has had here.

Anyone with any views? Please enlighten me, guys.

Typical British Bank Holiday

In England, there are certain "Mondays" in each year that are deemed "holidays". Examples are Easter, Jan 2nd, late August and Late Spring. The two last ones were laid down for Man to "enjoy" either what was left of summer, or the prelude to it.

It is the opportunity for many people, especially older ones, to get away for four days to warmer climes.

However, the British Public know better, and the words " Bank Holiday"{ have become synonymous with the words "windy, rainy, cold".

Many scientists see it as proof that Britain really has a climate called "Cool Temperate Western Margins"

Yesterday was a fine example. Cold weather, high winds and rain were prevalent throughout these Isles, and yet, the British, stiff upper lip never wavering, went on a mini-holidays in droves. The picture shows a family in Cornwall having a "lovely day out" on the side of a small hill overlooking th Atlantic. To say these people were optimistic is like saying Muhammad Ali was "The Worst.

...and as the afternoon waned, it heralded the return of the parties in question to the homeland. The writer was actually in a pub (-lic house), when all of a sudden the skies went really black and we were treated to a lightning storm complete with hailstones (Yes, hailstones, after having the warmest April on record). In the middle of this, a coach pulled up and out straggled (and soon to be bedraggled) several severals of Wiser Guys (old men past 80) to plunge into our pub.

Six sat down at my table.

Oh the travellers' tales! But none of this "Grumpy Old Man" attitude, for each one was as happy as can be, and all with smiles on their faces regaling me with tales of "that pub in Leamington Spa" and the suchlike. We all got talking and it seemed that Spring and Autumn has married well, at least until the hailstones stopped. It seems I was very popular to talk to until a reminder about "getting home to the wife" came about.

All in all, a Typical British Bank Holiday!

Calculus – such a complicated-sounding word!

This is the Akiko take on the calculus, a subject very dear to her heart as she has used it almost every day of her life since about 18.

What is it? Basically, it is a way to express quantities very accurately in the mathematical sense. For instance, what is meant by the simple word “speed” (and I am not talking Keanu Reeves here, nor even a “Keanu” coke)? Well, “speed” is a measure of how fast some thing is going. In other words, how fast the distance is changing in terms of time.

NOW, we got that started, we can move it swiftly on, with some Speed (and not even a hint of Coke or any other addictive substance). .
Physics, and mathematics, are very demanding in terms by what is meant by what one says. To take an example, try that phrase above “how fast the distance is changing in terms of time”. We used this descriptive phrase to describe “speed”. But we need to be more precise so we can actually do some calculations on it (calculations such as what will the speed be in 2 seconds’ time, a weeks’ time, how long it will take to slow down, and any more you can think of). That is, we need to quantify it .

First we have to work out what we ourselves actually mean when we talk about speed. The word “speed” actually means how fast. The drivers in you, and indeed almost everyone, knows what kph means. “kph” means “kilometers per hour” and is a number giving us how many kilometers we have traveled in the last hour, up till “now”. The “now” is needed because we need to know when we made this measurement. Let us say it is 60 kph, to make things easy.

So , in the last hour , we have travelled, on average about 60 kilometers. I say ”on average” because half an hour ago we were in a traffic jam, and 20 minutes ago, the backlog finished, and we reached the end of it and were able to travel up to “80 kph”.

So, if we measure our “speed” over the last half hour, it still says roughly the same….or does it….? And what was this speed when we were in the traffic jam? Update coming soon!

Fusion, fact or fable?

As I intimated last month, there is another way to get nuclear power, and it is called fusion. Because of the way this ‘new’ force works, it likes to stick together protons and neutrons, but at a price – it only does this for very short distances, and if that separation is approached (as in a BIG nucleus), fission occurs, and the nucleus splits apart, giving a whole new meaning to ‘a Big One’. It is rather like a spring which, if stretched, suddenly ‘snaps’, and whatever was at either end, flies off.

If these particles get too close, however, the opposite happens, and they are ‘sucked in’ by the ‘new force’. Once this has been done, it is very hard to get them apart again, but when they are prised apart, a new and altogether useful phenomenon occurs: you get more energy out than you put in!!!

Simply put, if you ‘weigh’ four atoms of hydrogen, push them together, trying to overcome the mutual repulsion of the static charges, you will make an atom of helium. This is because if the ‘new force’ comes into range, it snaps in, and literally sucks them all in to make one atom of helium. Now if you ‘weigh’ what you have left, one helium atom, you will find that the mass is just less than the four hydrogen atoms you had to start with. So where has the mass gone?

This question of the ‘missing mass’ is very easily calculated by a well-known formula, E=mc2. That is, multiply the number for the speed of light by itself (’square it’). Then, take this answer and divide the energy input by it, and the numbers that ARE the missing mass are there. Where? Well, it has been radiated off as gamma waves, which have enough energy to ‘carry away’ the missing mass. If zillions of these nuclei do the same, the effect is enormous and if harnessed, could be very useful. You see, the only fuel you need is hydrogen (the commonest element in the Universe).

How is it that this energy appears to come from nothing? Well, it does not, as the particles needed are reluctant themselves to come together, so we need to put them together ourselves. It is a bit like a shy home-boy at his first party. You have to put him, albeit reluctantly, into the fray, for him to just realize how much fun it is, and then he will find it hard to leave once inducted!

So it is with fusion. Fusion is so terrific that many scientists are trying to overcome ‘ignition’ (See post 1), but is so hard, fission is the only option, or seems to be.

So…..

Fission? Fact.

Fusion? Future Fact.

Fission, fiction or fusion….?

Unlimited power and clean, green, CFC-free electricity. Sounds like a fermi story, but actually that reality is closer than anybody thinks.

Except for people like me, that is. Even though a student am I; a scientist I am and the future I build.

I am jabbering in Huttese about the so-called nuclear power. A lot of people are scared of this, and rightly so, it is DANGEROUS.

But in actual fact there are two kinds, the dangerous kind, and the safe kind. Mankind so far has only been playing around with the first kind, but has long been aware of the second kind. This is the kind that is completely safe.

So why don’t we use the second kind? Simple answer is, it is very difficult. Easy in principle, hard in practice. Bit like an oversexed spotty schoolboy, really.

So what stops the second kind being used? Simply put: The Engineers. No, I am not referring to the ancient soccer team who won the English FA Cup eight times in four years, but back when there were only three teams in it, sometime in the late half of last century somewhere. I am talking about that group of guys who make money out of the ideas that this group of guys come up with. The Engineers. WE are the scientists.

Nuclear Power (No 2) is so difficult that it has to generate the temperature of a star in the lab. Generating this is easy, our team do it all the time (albeit for around the fraction of time it takes Tom Cruise to change partners), but starting it and getting it going so that it does not uncontrollably stop (rather like an impotent priest) requires more energy than the mini-star puts out.

We call this bit “ignition” because it goes self-sustaining (rather like an impotent priest on Viagra).

Incidentally, both Nuclear Power types produce the “Atom Bomb”. The first is called the “fission” bomb, which causes energy by flying apart atoms, and the second, “fusion” or “hydrogen” bomb, which causes energy by “sticking together” atoms. However the second is far more powerful because it requires a “fission” bomb just to ignite it. (or, in the schoolboy’s case, to stop it).

Imagine if we could gather that energy and use it. It is not impossible, but very, very hard (no comment about schoolboys or priests).

The way each version of the Nuclear Power needs a certain knowledge of nuclear physics, so only those really interested will be looking at the follow-up to this – “Fission fact, and Fusion”.

Just what IS Quantum mechanics?

This is a question that has been been asked many, many times.

Now, let's get one thing perfectly straight - the "mechanics" bit up there bears no resemblance to the kind of mechanics we usually talk about, such things as engines, nuts, bolts, screwdrivers, wheel- balancing, etc.

True, it is the same word, but in physics it means something very different and quite specific: "mechanics" in physics is nothing more than the study of the relative movement of things, like apples dropping from trees, billiard balls moving on a snooker table, and the occasional hammer hitting someone's head.

Nothing to do with cars or anything Richard Anderson might say in "Forbidden Planet".

A lot of the time, mechanics just deals with things hitting each other. When I say "deals with" I mean we use equations to find out where they will go next.

For example, what happens when two billiard balls collide, head on? Well, if one is standing still, the moving one hits it and transfers the motion, and the second one moves off.

In an ideal world, yes, but this is not what happens. It so happens that both balls end up moving. "How can this be?" I hear you ask. The answer lies in the way the balls are put together and what they are made of, BUT that is the realm of materials science, not physics.

So mechanics is when things hit other things. Now we're getting someplace, as Ollie would say.

There are different types of mechanics, all of which use the basic "mechanics" laws set down by Isaac Newton. There is Celestial Mechanics (how large things like planets behave), Terrestrial Mechanics (hammers hitting heads), Car Mechanics (nothing to do with this discussion), and Quantum Mechanics (how very small things behave, things like atoms, etc). Oh and there is Relatavistic Mechanics, and Relativistic Quantum Mechanics, too, but both these only come into play when you are travelling just a tad faster than Richard Hammond did last year.

So, WHAT is Quantum Mechanics? We, like I said, it is "how small things behave" but there is more to it than that. Scientists thought terrestrial mechanics ruled ok, ino questions asked, including the very small. The fact is, we had to invent a completely new branch of Mechanics, so as to predict where things ended up after the charabanc. The reason was, the very small particles acted in very different ways to what we expected. They actually acted like "waves". Hard to believe , ain't it? Moreover this "quantum Mechanics" gave right answers for all the other mechanics branches as well.

Depending on the experiment you were doing , the very small particles act both like "waves" and "particles". It is very hard to imagine, and even to this day 99% of scientists don't really know what is going on, BUT, what they DO know is how to predict what will happen when two of these "quantum" billiard balls collide, and what happens afterwards. Very clever.

So where does that leave us? Well, to the ordinary layman, you or I, it means nothing, because we as people are never going to deal with things THAT small ( I am saying nothing about Marvin's brain here), but some scientists have to deal with this every day.

They are called "particle physicists" and live in very tall ivory towers in Geneva. I, the layman (or laywoman) deal with particles just as small, but I am only called a lowly "nuclear physicist".

However, I still find fun mucking about with the equations in our computer programs, investigating "Quantum Mechanics". It is almost all a little girl can do.......

So, when it comes down to it, we have a perfectly good representation of the world as we know it with "Terrestrial Mechanics", so why do we need "Quantum Mechanics"?

A good question, and one which deserves an answer. With no Quantum Mechanics, we would not have discovered Light Amplification by the Stimulated Emission of Radiation, or the LASER. There would be no nuclear or particle physics, ie neither the Atom bomb nor the Hydrogen bomb would have been invented. Is that a good or a bad thing (bad for me, anyway!) - one for the philosophers, I am sure.

Another thing is that wihout Quantum Mechanics, we would have primitive computer controls still, the most important of all would be - no DVD's CD's etc, Guided missiles would be out too, as would be supermarket checkouts. TV remotes. The road goes ever on.

Maybe the most important thing we would be missing would be the Josephson Junction in electonics, but I wll leave the reader to find out what is THAT by himself.

Shrodinger will never know what a Pandora's Box he opened!