The Laws of Physics
by Anthony Bright-Paul
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Do you suppose that before Newton saw that famous apple drop to the ground, do you suppose before he formulated the law of Gravity, do you suppose that people did not understand that law long before he defined it? Of course they did.
The Norman archers at the Battle of Hastings certainly did as they shot their arrows high into the sky to fall with deadly effect right into the eye of poor King Harold. |
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They knew with absolute certainty that those arrows would not fly forever towards the Heavens but would certainly fall back to Earth. In fact this is the wonderful thing about most of the Laws of Physics. Although they maybe formulated in the classroom, sometimes with fancy names, immediately that we understand them we find that they relate to the facts of our experience. We may not understand the mathematics, we may not understand the how and why, but we do understand quite clearly that they are that they are facts, that they are true. The 1st, 2nd and the Zeroth Law of Thermodynamics is, or should it be ‘are’, a case in point.
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Do you imagine that an ancient smith in his smithy with his bellows heating up iron to put a ring round a wheel, or a shoe on a horse, do you imagine for one moment that he did not understand about conductivity? Of course he did – his life depended upon it.He may not have known the laws, he may not have known the words conduction, convection and radiation, but he did not need to know these concepts, because he knew them as a fact of experience. He could see that the smoke went upwards through the chimney, he could feel the heat radiating from the hot coals and from the glowing iron. His classroom was his life and his work.
Did he need to know the Clausius statement that heat always flows from hot to cold and never vice-versa, as he plunged his red-hot irons into a trough of water? No, he knew for a fact of experience that what is hot will certainly become cold in the course of time.
Now it is sometimes said that ‘entropy’ is a difficult concept. Really?
It would seem to me that Gautama the Buddha understood this, thousands of years ago. After all it was entropy that set him off on his search for enlightenment. Certainly as a splendid and athletic young man as he saw before him old people and dying people, and as he pondered about old age and death, facts of life that had been shielded from him, certainly he would not have formulated anything about high entropy and low entropy. But he would have known these laws just the same, just as most of us know these laws. We know very well that an acorn has high entropy; that is because an acorn has the potential to become a mighty oak and to live in splendour for three or four hundred years. As I am now 81 I am increasingly aware that I have low entropy and no matter how hard I try to keep active in body and mind, however careful I am of my diet and exercise, this bodily mechanism in which my I is encased is decaying inevitably.
The birth of a baby is always greeted with joy – why? Because the baby has high entropy, has the potential to grow into manhood or womanhood. And if a young person is struck down too young, as many soldiers are, we grieve because they have not had the time to achieve their true potential.
Not everyone I know has even heard of the adiabatic lapse rate – however anyone who has gone up Snaefell in the Isle of Man, even by the mountain railway, or anyone who has climbed Goat Fell in the Isle of Arran, or climbed upwards anywhere on a mountain, anyone will know for a fact that as they go up it gets colder and the air gets more difficult to breathe. The Physicist may be able to explain why with altitude it gets colder, why there is snow on the tops of mountains, but nobody doubts the facts of their experience. As I have bathed in midsummer in the Lac de la Cavetaz at Sallanches in the Haute-Savoie, I have watched with delight the enormous snowcap on the mountain so rightly called Mt Blanc. How gloriously, gloriously shining white is Mt Blanc!
Do you imagine that the ancients did not know about TSI? Of course, they would not have called it Total Solar Irradiance, but those whom we somewhat naively term sun-worshipping pagans undoubtedly knew that the sun was the giver of light and warmth and the prime driver of climate. Indeed, if we were not beset by a barrage of misinformation, we would all know that the sun is just that – the driver of climate. Of course, the worship of the sun is not a thing of the past – indeed it has never been more prevalent than it is today. The tourist industry is largely based on the fact that the majority of Holy Day makers head for the sun if they possibly can.
Professor Brian Cox in his latest TV series ‘Wonders of the Universe’ assured us that the Arrow of Time can never be reversed.
I wondered why he should make such a point of something that is seemingly self-evident. But put into context, not just with the motion of the Planets round the Sun, but also with the fact that the whole Galaxy of the Milky Way is revolving in stately and massive progress I began to see why Time is in fact a Law of Physics. It may take the Milky Way some 250 million years to complete an orbit, but what is certain is that not one iota can be reversed.
Once again one can say that this Law was grasped in its essence long, long ago by the Persian Poet, Omar Khayyam:
The Moving Finger writes; and, having writ,
Moves on: nor all thy Piety nor Wit
Shall lure it back to cancel half a Line,
Nor all thy Tears wash out a Word of it.
What the poet says corresponds to the facts of experience. Georgy Ivanovich Gurdjieff in his massive allegorical work “All and Everything” referred to the passage of Time as the Merciless Heropass.
So that when an esteemed colleague of mine declared that ‘the overarching issue is climate change and how to reverse it. We have a brief window of opportunity, and unless we act now the chances of avoiding a serious collapse are remote’ it means that he has not understood a fundamental Law of Physics. He can no more reverse changes of climate than he can reverse the revolutions of the Milky Way.
He was working on the assumption that man can and does control climate. This is a completely modern-day and atheistic heresy. I would even say blasphemy in the truest sense of the word.
What the Physicist is asserting, what the Physicist is examining are the Laws of Creation and the Laws of Destruction – Vishnu and Shiva in the Hindu pantheon. Unwittingly, even though he may think otherwise, the Physicist is a de facto theist.
Anthony Bright-Paul
March 28th 2011.
Just for Fun
A Question of Physics
by Anthony Bright-Paul
Answers by Hans Schreuder, webmaster of www.ilovemycarbondioxide.com
There is something that still puzzles me. If the sun is a great ball of fire it is radiating out heat. If that is the case then the nearer you are to the sun you should be hotter.
Correct. But that’s only because you or the vehicle in which you travel has mass to it.
Therefore outer space should be really hot. But I understand that it is really cold. Why?
Two interlinked errors here ….
1. outer space is a vacuum and thus has no mass within it to have a temperature. Any vacuum is devoid of matter and thus devoid of a temperature … temperature is a measure of the flow of energy.
2. As per 1. above, outer space is not freezing cold either ….! It has no temperature! The confusion comes in with the concept of a Cosmic Background Radiation, which is in the order of 3K (three Kelvin, equivalent to minus 270°C). That CBR is “measured” by looking through trillions and trillions of miles of the vacuum of space and thus the odd molecule of matter that really does have that 3K “temperature” ends up being registered on super sensitive IR “thermometers”. Various words are in “” because they do not fit the usual meaning of those words.
To add to this confusion, any matter in that vacuum of outer space and not in receipt of any stellar (solar) radiation either is or will get colder and colder until it reaches that same 3K. Why? Because all matter radiates when it has a temperature above zero K, the absolute zero point of all matter, and the point where no further radiation is possible. So, in the absence of stellar (solar) radiative input of energy (in our case sunlight) any matter in outer space will continue to lose its energy by radiating until it gets to the CBR level of 3K.
The sun’s rays pass through the atmosphere. Correct?
Not all of it. Approximately 25% of all sunlight that reaches our earth’s outer atmosphere (a poorly defined region between 30 and 100km off the surface) is either reflected straight back into outer space off particulates (dust) in the atmosphere or the tops of clouds or scattered by infrared reactive gases such as water vapour and carbon dioxide and to a small extent the oxygen and ozone molecules as well. See this graphic to get some idea of the losses and the “absorption bands”:
The top of our atmosphere, the Troposphere is extremely cold. The tops of mountains are cold. Yet the surface temperatures are hot, which are farthest from the sun. It seems illogical.
That has to do with the reactivity to radiation of the substances that are hit by that radiation. As per the previous point, some 75% of solar energy goes straight through the atmosphere and thus has no effect upon the air temperature. When that 75% of solar energy hits the solid earth or the water in the oceans, rivers and lakes, those substances are heated to varying degrees, depending on the specific properties of the material receiving that solar radiation. You will know from direct experience that a wooden bench feels less cold than a metal bench in winter yet warmer in summer. That’s because wood has a lower specific heat. So, when it is cold, wood will feel less cold than a metal object yet warmer when the sun is out. This has also to do with the rate of heat dissipation, so not an easy concept to explain in a few words.
The atmosphere has no heat of its own. Correct? The sun’s rays strike the ground. The immediate atmosphere becomes warm to a certain level. However if one sits in the sun one feels the heat from the sun. Is that an illusion? If a cloud passes it feels cooler.
Another tricky one to explain in a few words …! The atmosphere does have a temperature of its own but it has a low thermal capacity – example of thermal capacity: put a sheet of thin aluminium foil in the oven and put it on top of a ceramic dish. Let the oven be at 100°C only, so as not to create too many blisters … Now, after 15 minutes or so, open the oven door and grab the foil with your bare hands …. I bet you will not get one blister and barely feel the heat of the foil; do not do the same with the ceramic dish, for obvious reasons! Explanation: the ceramic dish has a hugely higher thermal capacity. In fact, put that 100°C dish on a heat-proof surface, using oven gloves, and check its temperature after, say 15 and 30 minutes. Still warm, right? Yet that foil that came out of the same oven at the exact same temperature lost all of its heat in seconds. That’s what’s called thermal capacity.
So, back to the atmosphere. Air has a low thermal capacity which is however greatly affected by the level of water vapour. The higher the humidity, the less the effect of a cloud passing overhead. Why? Because water vapour has a huge thermal capacity. So huge in fact that even nuclear reactors still use steam-driven generators to create the actual electricity they deliver! Gas, oil and coal-fired power stations all use steam-driven generators! That’s also why the “age-of-steam” was such a gigantic leap forward in our industrial revolution. It is still used in our 21st century electrical generators!
If I light a bonfire it is very hot close to – scorching. Five yards away it is tolerable. 15 yards away I can see the flames but experience no heat.
Correct, that’s due to a double-whammy effect: 1. convective heat-dissipation; 2. adiabatic heat-loss.
1. Any gas molecule that is only slightly warmer than its surroundings will have a lower specific gravity and thus become relatively lighter than its surroundings and thus floats away upwards.
2. Any gas that expands loses heat in so doing, called the adiabatic effect. That’s why the higher up in the atmosphere you go the cooler it becomes – even though that is only half the explanation, as the atmosphere has distinctly warmer zones higher up, but that’s another story and a different set of effects … sorry to make it so complex, it is complex!
The only heat that you end up feeling directly after only a short distance away from the fire is the direct infrared radiation, which is distinct from the direct contact with the heated air.
Check this graphic to see how all known atmospheres have a kink in their temperature vs altitude correlation:
and to make it even more confusing, here is a close up of our own atmosphere:
The sands by the Med get so hot to the feet that one has to wear sandals. Yet two hours after dusk these same sands are cold. Correct?
Yes, that is because the atmosphere will carry the heat away each and every second of the day, as per the above explanations. Also see my latest essay on that issue, attached. Sand has quite a high thermal capacity, that’s why it takes a few hours for it to cool down. Hot rocks will cool down slightly slower, but cool down they will, even in the highest humidity zones. The only difference will be the rate of cooling, never the action of cooling as such.
Can you explain?
I’ve tried … let me know if I have succeeded.
PS 1
For Green read Greed!
by Anthony Bright-Paul
I am faced with a problem – on the 5th of May I have a chance to cast my democratic vote. But the question is this – should I vote for the Conservative Greens, the Liberal Greens or the Labour Greens. Personally I do not want to vote for any Greens at all, for what does Green stand for now? It should stand for saving the environment, but it is now inextricably bound up with its destruction. Wind turbines creep over Europe and North America like relentless mange, a sort of unstoppable ringworm.
The Greens should be for all that is green, but anyone half educated knows that their war on Carbon Dioxide is a war of complete ignorance. Anyone who has the most basic knowledge of Biology knows that Carbon Dioxide is a food for plants. Great nature has so arranged it that by photosynthesis plants turns Carbon Dioxide into Oxygen for us to breathe. But they are for banning CO2 and for demonising it with their absurd Carbon Footprints, or even for sequestering it under ground. So we have a Minister of Energy in this dread coalition, who is apparently unable to distinguish between Carbon and Carbon Dioxide. I doubt whether most MPs of all parties are even able to distinguish between Carbon Monoxide and Carbon Dioxide. They hope that we shall all be mugs.
So I have a dilemma. Should I vote for the Labour Greens? I seem to remember Gordon Brown suggesting that we have only 50 days to save the world and that was back in the halcyon days of Copenhagen. They tried to get an agreement to limit temperature rise to 2° Celsius. No, I am afraid there is no way I could vote for Labour Greens, if they are so wacky that they imagine that they have control over the various temperatures of the Earth. The sheer wooliness of the thinking really puts me off.
So how about the Liberal Greens, lead by that Minister of the Crown, Chris Huhne? I am afraid here to speak my mind, I am afraid here to express my contempt for this man who brushes aside the concerns of people through this once green and pleasant land, but which is now blighted by thousands of his useless wind turbines. The odium that attaches to his name unfortunately spreads to all around him.
And so we come to the Conservative Greens. From the Conservatives I had held some hope. They were for balancing the books. Of course, like all politicians they told us, the electorate, that we must draw in our belts, as if we were overspending, as if we were having it too rich. Not so! The majority of middle England strives to live within their means. It is Governments who spend more than they earn; it is Governments who enter into huge mortgages in order either to bribe an electorate with their own money, or to provide them with goodies from the IMF. So we would have expected a Conservative party to lead the way in matching expenditure with income, in reducing our National Debt. Is that not what economics is? Every salesman who has ever sold Life Insurance knows the truth of this. If the main breadwinner dies, how is the income for the widow or widower to be replaced?
But what has happened? With a sleight of hand worthy of Gordon Brown, who introduced by stealth one tax after another, our Chancellor has evidently taken a leaf out of his book. He introduces a Budget that is supposed to help industry, but hidden in the small print, introduced at the end of his speech, is his intention to introduce Green Taxes, the import of which could not be taken in at once. Thanks to a wonderful article by Christopher Booker we can now realise the full ghastly import.
It is his intention to ‘green the grid’. What does that mean? It means that he is going to tax our Coal and Gas Power Stations until they are as uneconomic as those wretched Wind Turbines.
Now you will understand my dilemma. I cannot possibly vote for a Conservative Party who deliberately intends to destroy our industrial base, what is left of it, and to make electricity dearer for the old, the pensioners and the sick. And all this in the name of being or going Green! It is enough to make one green with vomit!!!!! Believe me, I am a natural conservative, but I am never a Green. Mr Osborne, Mr Cameron I urge you now to distance yourself from the odium that will attach to policies that will destroy our country.
The success of England in the past, the success of the United States of America, the huge success of our kith and kin in Australia and in New Zealand, has all been built on cheap energy. To deliberately make our energy, our electricity, dearer than everybody else’s worldwide is a betrayal of your people’s trust. I call on every true conservative to haul you back from a truly momentous mistake, from which you will never be forgiven.
How come that such a policy could ever be formulated? The answer is as simple as it is obvious – it is not being driven by Green, but by Greed! Ask yourselves, and the electorate will also ask, who is making a pretty penny out of driving the Wind Turbines that don’t work, and that are hideously expensive? Who holds shares in these wind turbine companies? Who has an interest? Who allows these monsters to be built on their land, or their seas, as long as they are not built right next door to these owner’s homes? Cry havoc! The whole thing stinks to high heaven!
And to imagine that this whole nonsense started only a few years ago with a scare story about a trace gas in our atmosphere that is so minute that it is like this:
I ask you.
Anthony Bright-Paul
PS 2
Dr Bratby takes Chris Huhne apart
“By the end of this decade, the UK must cut its carbon emissions by 34% on 1990 levels.”
I hope when you say carbon, you actually mean carbon dioxide. We do not emit carbon. This is sloppy language – we don’t say hydrogen when talking about dihydrogen monoxide (water), so why say carbon when talking about carbon dioxide?
“As the Chief Executive of Natural England said, climate change is ‘the biggest issue facing the natural environment’. I am, of course, am preaching to the converted”.
The Chief Executive of Natural England was wrong and you most definitely are not preaching to the converted. CPRE is a broad church and many members of CPRE, at the grassroots level, particularly those with hard science and engineering backgrounds, such as me, do not accept the hypothesis that humans are changing the global climate. The hypothesis that recent climate change is natural has not been disproved. There is no evidence that human emissions of carbon dioxide are changing the global climate. If you have such evidence, please publish it here.
Everything you state under the heading “English Impacts” is pure nonsense and is not based on any evidence. The climate is changing naturally, just as it has for the 4.5 billion years that the earth has had a climate. The main threat from a naturally changing climate is that of a colder climate; either a return to conditions similar to those of the Little Ice Age, or as many are predicting, a return to ice age conditions. It has to be remembered that a warm climate with a carbon dioxide rich atmosphere is beneficial to plants and animals (including humans).
“We must do everything we can on the international stage to get an agreement to cut carbon emissions”.
Do you mean carbon dioxide emissions? If so, why not say it? We should be increasing carbon dioxide emissions as I have stated above.
“Providing clean, green energy to 2050 and beyond”.
What do you mean by clean, green energy? Gas-fired and nuclear power stations are clean and green, aren’t they?
“The first is renewables – like onshore and offshore wind, biomass, energy from waste, solar, marine and micro hydro power”.
From a purely physics aspect, these technologies can never provide more than a tiny fraction of out energy needs because they rely on a diffuse source of energy (low energy density) and thus are unsustainably expensive and unreliable.
“The third pillar is clean coal and gas, delivered by carbon capture and storage. Giving us flexible and reliable energy – without the carbon consequences”.
Again, I assume when you say carbon, you actually mean carbon dioxide. Carbon dioxide capture and storage will never work. It is energy intensive, prohibitively expensive and potentially dangerous. It should be consigned to the dustbin before more money is wasted.
“And the Treasury has announced a carbon price floor to underpin our signal to the marketplace – and to encourage low-carbon use of existing plants”.
A carbon price floor, without international agreement from all countries, will add to our energy costs and make the UK uncompetitive. Jobs will be exported overseas and yet again, the poor will suffer most.
“Early stage technologies like tidal power may be long established. Interconnectors could flourish, allowing us to trade natural resource strengths with our European neighbours. Concentrated solar power in the Sahara could create enough electricity for two continents. A technological revolution could deliver deep offshore wind at rock-bottom prices.”
Pigs may fly. Offshore wind can never be delivered at rock bottom prices. The reason is yet again due to the low energy density of moving air. This means large (expensive) structure, operating in a harsh environment where maintenance is nigh-on impossible and connection to land is difficult and expensive.
“But we know the carbon boundaries we must stick to if we are to keep global temperatures to within two degrees of pre-industrial levels”.
What is a carbon boundary? I assume you mean atmospheric carbon dioxide concentration. We have no idea how much carbon dioxide in the atmosphere will result in a two degree rise in global temperatures. The projections are based on computer models which have zero validity. The climate is a non-linear spatial and temporal chaotic system which is impossible to calculate. Even the IPCC admits that climate models have no validity.
“Onshore windfarms demand careful location and siting”.
In that case why does the planning system allow wind farms to be located in most inappropriate locations in the countryside too close to dwellings and in many cases where wind resources are poor?
“Nuclear power means tight safety standards and a long legacy”.
Nuclear power currently has unnecessarily tight safety standards (that is why nobody has been killed in the west by a nuclear accident at a nuclear power station). Other power generation systems regularly result in deaths – wind, hydro, coal, gas, oil, etc. The nuclear legacy is finite, due to radioactive decay, whereas the legacy from many alternatives is permanent.
“Some technologies will fall by the wayside as costs or progress make them unsustainable”.
Wind (onshore and offshore) have costs which are currently unsustainable.
“And in a world with more renewable energy, balancing the grid becomes more challenging”.
The first pre-requisite of the electricity network is ensuring that there is sufficient despatchable capacity to meet the peak demand. This means having sufficient despatchable capacity to provide baseload, to enable load follow and to respond to peak load. Despatchable renewables such as hydro can perform this despatchable function, whereas intermittent renewables such as wind, solar and tidal cannot. Therefore these non-despatchable renewables should be secondary aims of the UK’s future electricity supply.
“When it comes to onshore wind, communities should be protected from unacceptable impacts”.
When will the “should” be changed to “will”. At the moment communities are having inappropriate wind farms imposed on them.
“It will show how we will meet the 2020 renewables target”.
Getting 15% of our energy from renewable sources is an impossible political dream, committed to by Blair in a moment of madness. Without large hydro capability in the UK, the major emphasis is on wind power and already there are papers showing that any wind power beyond about 8 to 10GW will result in grid problems due to the intermittency and unpredictability of the wind. 10GW of wind power at a generous capacity factor of 30% will provide an average of only 3GW generation or 26TWh per year, i.e. less than 10% of electricity supply, which itself is only about 1/3 of total energy use. Hence 15% is a pipedream.
“Think about the grand prize. Cleaner air. More affordable energy. Less risk of climate change. A greater degree of energy independence. For the first time since the 18th century, we have a chance to return to a true sustainability: one that does not see low-carbon generation as destructive to the economy or the environment, but as fundamental to the integrity of both”.
It is not evident how subsidising inefficient renewable energy such as onshore and offshore wind and solar PV will lead to more affordable energy. The experience of Denmark and Germany is that wind power does not lead to cleaner air or reduced carbon dioxide emissions because of the constant need for operation of coal and gas-fired power stations as back-up for when the wind falls. Where has the coalition examined the implications of the operation of conventional power stations in back-up mode on the cost of electricity and on carbon dioxide emissions?
Why is the coalition wasting money on ineffective and expensive wind power when future secure supplies of clean and green electricity could be obtained from thorium MSRs at a fraction of the cost?
About Dr Phillip Bratby
Dr. Phillip Bratby has a first class honours degree from the Imperial College of Science and Technology (London University) and a doctorate in Physics from Sheffield University. He is a semi-retired energy consultant and the sole director of a consultancy company.