Physics and the Authoritarian Need for Control

I believe that the principle that guided early scientists was the belief that all things needed control. As examples:

                Animals must be tethered or retained by fenced fields

                Soldiers must be disciplined

                Workers must be (micro)managed

                Machines must be controlled

                God controls the Universe

                Etc

I’m sure you get the point.

Thus Newton’s mechanics are full of control.

A body remains in a state of rest or of uniform motion in a straight line unless acted upon by an external FORCE.

Bodies remain in orbit because of the gravitational FORCE.

STANDARDIZED measures were proclaimed.

Thus laboratory experiments, naturally, were performed within constraints. Gas would be in a container so its volume, pressure and temperature were CONTROLLED.

One can, of course, argue the necessity of all this, because experimental proof requires repeatability, and so on.

That’s all well and good. The question is: has this deprived us of a whole lot of understanding about the behaviour of space/time/matter/forces in uncontrolled situations? There are no fixed containers around newly forming stars. Have we got a false idea of the constant arrow of time?

Relativity has given us (among other things) an inkling of the need to think about different spacetime reference frames. In daily life we think readily of changes in spacial dimensions versus time, but always regard the passage of time as unvarying. What if it is spacetime that is fixed in its progression and the rate of passage of time is variable? If time “stood still”, space would have to expand, in order to compensate. (That might account for the inflation epoch in “Big Bang” theory).

What if there are no rules?

Personally I think chaos theory is misnamed. For me, “chaos” means “no rules”. Imagine if gravity was randomly variable versus time? Now that would cause real chaos!

While I admit I tend to think of probabilistic approaches to problems as being cop-outs for not understanding some underlying process, it does appear that there’s a lot of probability “going on” in the universe. Could it be that the laws of physics that we hold to be true are, themselves, random in nature, and we just happen to be enjoying a spell of apparent consistency?

Hold on to your hats folks!

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One for My Memoirs

Theoretical research is a mixture of highs and lows. I’ve been labouring away at the logical discussion; looking for the counter arguments and the means to counter them. “Ah but have you considered the effect of….”

One particular area was very logical and clear to me, but was missing a vital factor. Yesterday, for a break from something else, I did some of the Maths. I had already done some work on this before using figures interpreted from somebody else’s work, but since then I had acquired the empirical data and the re-plotted graph had confirmed the previous, rough, findings.

Looking anew at the graph, I then realised it also, apparently, supported a well-known physical theory, which had, so far, gone uncorroborated. If that theory was shown to be accurate, one of my last remaining logical hurdles was passed! The moment had arrived to do the statistical regression analysis and provide the equation that was the main purpose of the plot.

Maple did its work, and once a couple of terms had been dismissed, because their value was well within experimental limits of error, I was left with a simple expression containing just one independent variable and one constant. Up till that moment I had not really looked at the numbers, just the form of the expression. I suddenly twigged that the one remaining numerical constant was in fact “c”, the speed of light: a totally unexpected outcome.

Rewriting the expression gave me such a beautiful equation; I just sat back in amazement. I now fully understand what all those eminent scientists had meant about beautiful equations. Result: corroboration for part of my theory, corroboration for another man’s work, and one of the most beautiful equations I’ve ever seen.

Sorry but you’ll have to wait for publication to find out what it is.

Meanwhile, what’s “c” doing there? That’ll be another new chapter, then.


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Earth to Mars and Back

I haven’t got time to do this, but it got under my skin, after a conversation on Facebook, and I have to get it off my chest!

Going from Earth to Mars seems fairly simple in concept. OK it would take a few months, but it is our next-nearest planet, so what’s the problem?

First let’s point out that while the Sun’s gravitational field dominates the solar system, this is largely overcome by the orbital force requirements of the planets. Any object going between planets is assisted in part by the orbital speed of its launch planet. The Sun becomes a factor in determining the net orbital path of any object such as a space craft.

Going from Earth to Moon is fairly straightforward because, in astronomical terms, the Moon is only a short distance away and the Earth and Moon, being in similar solar orbits, largely cancel out the Sun’s gravitational pull.

Going to Mars is a different story. The space craft effectively has its own solar orbit, the speed of which must overcome the gravitational force of the Sun. It’s going to be hard work to get to Mars, in terms of rocket power, and on the return trip, the problem will be in slowing down, because the space capsule will have been accelerated by the Sun to very high speed, relative to the Earth. Position of the Earth in its orbit at both launch and return will be critical in terms of matching speeds.

Now consider this. During a 501 day trip, in round figures, Mars will complete 0.73 orbits, Earth 1.37, Venus 2.23, Mercury 5.69 and Jupiter 0.12. So, at different points during the trip, all the inner planets will change relative positions significantly and may have a part to play in influencing the space capsule’s progress. You may be surprised that I included Jupiter but it is so massive. The other inner planets although much less massive, could well interpose, in gravitational terms, between the Earth and the capsule at some point in the flight.

I would love to see a computer animated simulation of the 5 inner planets and Sun and their gravitational wells at the various orbital juxtapositions they will occupy during the 501 days of the planned trip.

Here are some interesting comparative numbers (source data from OU modules S282 and S283).

Note: All masses and distances are relative to Earth's. Periods are in days.

The relative gravitation figures are as experienced at Mars’ position. These are mass relative to Earth divided by distance relative to Earth’s orbital radius (Astronomical Unit) squared. Mass of Mars and gravitational constant are common so excluded. We can readily see that Venus’s influence at nearest to Mars (1.27) exceeds Earth’s at its farthest (0.16).

Note that Jupiter’s influence at Mars, even at its farthest distance (7.04), is greater than Earth’s at its nearest (3.70)! Mercury doesn’t figure at all (no surprise there).

The Sun’s dominance is all too clear! You can see what the capsule will be up against!

Then let’s not forget the asteroids flying about.

 

		Relative	Orbital		Orbs in	Nearest	Relative	Farthest	Relative
	Planet	Mass	Radius	Period	501 days	Distance	Gravity	Distance	Gravity
	Sun	332775.9	0	0.00		1.52	144033.90	1.52	144033.90
	Mercury	0.055	0.39	88.00	5.69	1.13	0.04	1.91	0.02
	Venus	0.815	0.72	224.70	2.23	0.8	1.27	2.24	0.16
	Earth	1	1	365.30	1.37	0.52	3.70	2.52	0.16
	Mars	0.107	1.52	687.00	0.73	0		0
	Jupiter	318	5.2	4332.46	0.12	3.68	23.48	6.72	7.04

The Fermi Paradox

“The Fermi paradox (or Fermi's paradox) is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilization and humanity's lack of contact with, or evidence for, such civilizations.“ (Wikipedia)

If you had moved home to a new location far away from your previous one, and wanted to go out and make friends, which of these is least likely as a place to look:

            Sporting club?

Social club?

            Educational institute (e.g. evening classes)

Special interest group e.g. Astronomy society?

            Street full of knife-wielding brawling drunks?

I’m assuming you picked the last as the least likely.  On that basis, why would inhabitants of another planet pick Earth as a planet to be friends with?

For all we know, we were visited in the distant past and have been shunned ever since because of the constant warring.

That, I believe, is the explanation for Fermi’s paradox, and, incidentally, why SETI is a bad idea. We need to be careful whose attention we attract: there could be planets out there whose inhabitants are even worse than ours.

Astronomy and Global Warming

An Astronomical society friend has commented that there seem to be fewer clear skies since he bought his telescope.

When I heard about global warming, I got an impression (shared, I suspect, by many) of rising sea levels and the weather becoming more prone to storminess. The main message, apart from “stop making CO2” was: “live away from low ground”. And there was the bit about the conveyor belt turning off and causing a mini-ice age around the British Isles.

The increasing propensity for flooding has shown (to me) an unsuspected aspect: that of higher humidity and rainfall due to the warmer atmosphere.

When the ice melted after the ice age, the air temperatures were relatively low, so the extra liquid water stayed in the sea, raising sea levels. At the relatively warmer air temperatures of today, the glacial  melt water is evaporating, raising humidity levels, increasing cloudiness and producing more rain; hence the flooding. Also, I suspect, this process is maintaining the salinity of the oceans and, with it, the operation of the conveyor belt.

So the message is not so much “stay away from low level” as “stay away from rivers and valleys”. And councils need to make sure there is good road drainage, especially on hilly roads. Last winter, when returning to Sussex on a wet evening, I was appalled at the large puddles in the right hand lane of the M4: a recipe for disaster.

I wonder how many people are aware of the latent heat of fusion of ice. Ice doesn’t automatically turn into liquid water at 0 degrees Celsius. The ice requires a further dose of heat to change state from solid to liquid. That’s called the latent heat of fusion. It is possible for ice to be raised to 0 degrees just before winter, then, effectively store heat until the following spring, when it finally melts. This might help to explain why unexpectedly large pieces break off from polar glaciers. The recent BBC TV programmes Operation Iceberg showed that there is still a lot being learnt about glaciers and icebergs

Longer term, the situation is more complicated, goes further.

With the increased cloud coverage we will presumably see a greater greenhouse effect, which implies accelerated global warming. Our “evil twin” neighbour, Venus, is completely engulfed in cloud, and its surface temperature is 560 degrees Celsius; not a comfortable place to be.

Venus is about two thirds of our distance from the Sun, which means that, under the inverse square law, it gets more than double the Sun’s radiant energy, compared with the Earth. I suspect that Venus has much more internal heat than Earth: the extra radiation it gets from the Sun may have delayed the radiation of its own heat. Not only that, but its clouds are somewhat darker, (being sulphur dioxide-based) than our white water vapour clouds. That means that a fully cloud-shrouded Earth could display a higher albedo (the property of reflecting radiation) than Venus does. Currently Earth’s is much lower than Venus’s. The higher albedo of a cloudier Earth would deflect more of the Sun’s radiation, than currently, and could potentially allow the planet to cool itself down again. Once the planet has cooled, the polar ice could reform at the expense of the humidity and cloud cover, taking us back to “normal”.  So perhaps the Earth is self-regulating in that respect.

Clever planet is the Earth. There’s more to the Goldilocks zone than mere distance from the Sun!

Don’t hold your breath, though, it’s a very slow process.

Meanwhile, from an observational Astronomical point of view, and in the short term, I see a continuing reduction in the number of clear-sky nights for observing, and an increase in the need for dew management. Reputedly, a hazy sky yields improved seeing, so, at least, we should get clearer views when we can see the stars.

Conclusion: treat every clear night as if it’s the last!