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Physics, Astronomy & Cosmology / Re: Can entropy of an isolated system decrease if balanced?

« on: 16/05/2017 00:18:12 »

Another example: If you have two bottles of different gasses, and connect them by a narrow hose, and put them in the isolation box, then after a time they will tend to mix together and become an indistinguishable mixture when you take them out again.  What we would want to do is put them into the box initially mixed, and then on taking them out later find that they had unmixed themselves into their bottles. That, of course, is contrary to the Second Law, but it is here proposed that if one somehow processes the mixed gasses before insertion into the isolation box, that they could in theory be set on the road to self-unmixing, and that because the process for initializing the gasses would generate much external heat, the Second Law would not be violated. It is essential, of course, that the initialization process not itself unmix the gases . The gases at the time of insertion into the box must still be mixed in order for the experiment to be valid.

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Physics, Astronomy & Cosmology / Can entropy of an isolated system decrease if balanced?

« on: 16/05/2017 00:02:39 »

Is there any way to prepare a system, place a system in a box that isolates it from its environment, wait a while, open the box, and find that the entropy of the contents is less than when it was put in -- if we allow the entropy outside the box to increase by at least the amount lost on the inside of the box?  (The process inside the box would violate the Second Law of Thermodynamics if considered by itself, but if the entropy outside increases by a greater amount than that lost inside, it appears that no violation occurs.) For example, do something to a container of gas that sets in motion the generation of a lot of heat outside the box, then put the gas in the box, close the box, open it a while later and find the gas has liquified (i.e., now is at a lower entropy) but the Second Law is not violated because the heat generated by the initial process more than offsets the cold generated inside. 

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Physics, Astronomy & Cosmology / Re: Is sound affected by sunlight?

« on: 10/05/2017 04:19:53 »

Insofar as sunlight is affecting air temperature, it would affect sound propagation.

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Physics, Astronomy & Cosmology / Re: Would this magnetically-suspended ring spin forever?

« on: 10/05/2017 04:17:36 »

I believe experiments of spinning magnetic objects in a vacuum have been done, and they do keep spinning for a very long time. The main limiting factors would be residual gases and field asymmetries, the latter being significant (at practical speeds) mainly in the way they would interact with hysteresis and conductivity of nearby objects.

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Physics, Astronomy & Cosmology / Re: Can fog cause a rainbow?

« on: 10/05/2017 04:08:35 »

I too once observed the phenomenon.

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The Environment / Re: What is the role of radiative forcing in cloud physics?

« on: 10/05/2017 03:55:18 »

Radiation reaching the surface heats it, which in turn contributes to convection, which moves air upward. If that air is moist, it will tend to form clouds when it reaches the lower pressures of the higher altitudes. Radiation absorbed in the atmosphere itself heats it directly, which encourages it to rise while at the same time requiring it to rise further than it otherwise would have to form condensation. The precise details of how this all works out requires more meteorological knowledge than I currently have.

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The Environment / Re: Is infrasound used meteorologically?

« on: 09/05/2017 05:04:26 »

Very interesting.

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Plant Sciences, Zoology & Evolution / Re: Would deep sea fish survive unprotected in space?

« on: 05/05/2017 06:41:43 »

I believe the question has to do with the expansion of air and of water. If an organism containing no free air is brought up from the deep, the pressure has dropped enough for that air to expand, if it existed, but it does not. (Although you would think that dissolved gasses could, as with divers that surface too quickly.  Maybe this does happen, but is not expansive enough to produce an obvious external effect.) The pressure has also been reduced on the water, allowing it to expand greatly if only it were hot enough, but it is not.  However, if the organism is then taken to the vacuum of space, the pressure is reduced enough that water can boil, under which circumstances I would expect to see some serious bloating.

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General Science / Re: Can I use hydrogen peroxide as a wood restorer?

« on: 05/05/2017 06:33:40 »

I don't believe that hydrogen peroxide is an environment to which plants are commonly adapted, so that it would not be unheard of if plants did not grow well in it.

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Physics, Astronomy & Cosmology / Re: What will scenes look like if time conflicts?

« on: 01/04/2017 06:52:21 »

Tough problems can sometimes be solved by iteration. A provisional solution is obtained using simpflying assumptions, then that is used as the starting point for a more refined solution, and so on.

Using that method here, the first approximation would be that the window remains closed throughout. Therefore, basically, each observer takes his/her own picture in a mirror.  The camera flashes, the light bounces back, and is reflected, recorded, absorbed, etc. Visibility is limited to the brief interval when light is present.

If, with that in mind, we now look at the case that the window opens as described, when Observer A takes his picture, the light that is returned is (mainly) from Room B, not A; but the situation is otherwise superficially identical  . So we would expect no different outcome, we think. However, one point that has not been made clear in the original problem is whether the contents of Room A and Room B are identical. There is no compelling reason why they need to be, and the assumption that they are creates a complicating feature that limits the generality of the solution. Let us then look at the situation that they are not identical. Observer A wears a red shirt; Observer B wears a blue shirt. Room A has a Victorian chair, B a Danish Modern. A uses a Nikon; B a Minolta.  The walls in Room A are beige; those in B a light blue.

So Observer A, when photographing into Room B, is photographing Room B rather than a reflection of Room A. The implication of that is that the light from A's flash travels into B, where we think it is partly absorbed, partly reflected, and partly returns to A's film (or whatever) to make the picture.  But, in order for the action as seen by Observer B to be likewise from B's perspective, then the view of B's photography from the standpoint of Observer A, whose time is moving in the other direction, the light from B's flash starts (on A's clock) out by extracting itself from A's environment and B's film (resulting in the erasure of B's picture), recollecting itself, returning to B's flash, and recharging B's battery. But part of B's light was involved in some manner with A's camera, inasmuch as both shutters were open during the same short interval. Now we know under normal circumstances, when you take a flash picture of someone while he is taking one of you, both cameras will record te other's flash.  If A's camera does in fact "see" B's flash, we would expect this result. However, everything we have thus far seen regarding B's light is that it proceeds not to the objects in Room A (including A's film), but from them.  Thus, the conclusion is suggested that the light that normally would have recorded B's flash upon A's film, actually departs (by A's clock) A's camera rather than enters it, being generated for this purpose by A's film.  But if that is so, what state must A's film be in at the end (A's clock) of the experiment? One would think that A's film, when developed, would have to somehow look different than it would under the scenario that the window never open.  But what would the difference be?

This question brings up another:  In the iteration thus far, the effects of A's and B's light has been treated as independent phenomena whose results may be simply superimposed linearly.  That proposition, however, remains thus far unproven.  The solution thus far envisions light from B's camera, when viewd by A's clock, to extract itself from the energy in the environment and eventually end back up in B's battery (and vice versa for A.)  But that does not take into account the fact that the environment from which it extracts itself is, at some point, influenced by B's flash.  Does light that extract itself from an environment that is not influenced by any other light, still extract itself the same way from an environment that is?  Do the results of this experiment depend on the relative intensities of the flashes?  What if the intensity of B's flash is, say, .000000001 times the strength of A's flash?

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Physics, Astronomy & Cosmology / Re: Do far away galaxies appear to rotate slower than they are?

« on: 01/04/2017 05:20:51 »

How would you know what the velocity of the galaxy was initially if the velocity has been slowed by time dilation?

We must distinguish between the velocity and the relative rate of a clock located in the galaxy. They are not the same thing. "Time dilation" refers to the latter.  Also, in addition to time dilation per se, there is an additional apparent retardation from the standpoint of a terrestrial observer because of simple Doppler shift.

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Physiology & Medicine / Re: Why don't the Germans die young with their smoking beer drinking and autobahns

« on: 01/04/2017 05:09:03 »

It would be helpful if some firm statistics were available.

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Physiology & Medicine / Re: What is the science of gender designation?

« on: 01/04/2017 05:04:06 »

Of course, puppypower wants to blame the victims of painkiller addiction for their addiction. Yet study after study has shown that the recent epidemic of painkiller addiction comes from those who use them to treat legitimate pain under a doctor's care. Again, here is someone trying to control the lives of other people, who views addicts, women, and people following gender roles other than those puppypower approves as less than human.

A person who becomes addicted because he/she has taken painkillers under prescription to treat pain, is nonetheless addicted.  This is not a desirable outcome; but the prescribing physician has to weigh that risk against the alternative. Addicting painkillers may be suitable for pain victims by reason that the alternative is worse, but that does not make them suitable for other people, nor something that ought to be recommended in the general diet.

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Physiology & Medicine / Re: What is the science of gender designation?

« on: 01/04/2017 04:56:56 »

But notice that there is a huge difference in this analogy that puppypower wants you to ignore: if you only have sex for pleasure, you won't die. If you do not reproduce, then you are free to continue leading your life. It seems that, to puppypower, if you are not leading a life where you are reproducing, you might as well be dead.

Nevertheless, a life of sex only for pleasure carries a risk of negative consequences in the life you are free to continue to lead, and even afterward. There are well-documented disease risks associated with a life of promiscuity or "gay" living. Either of these manners of living probably may well close the door to those benefits of marriage that go beyond the bed. Also, a life of childlessness eventually means that the person will have  no children, at least none associated with his/her personal lifestyle, which can have negative implications for preparedness for old age, and if many people in a society choose to live this way, the demographic consequences for the economy can be ruinous, eventually undermining the social insurance systems that the public had depended upon to support them.

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Physics, Astronomy & Cosmology / Re: Does empty space have motion?

« on: 01/04/2017 04:35:42 »

Motion is a change of position. There being no reference point in empty space, there can be no motion.

What did the instruments that recently confirmed gravitational waves detect?

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The Environment / Is infrasound used meteorologically?

« on: 01/04/2017 02:10:37 »

It occurred to me that infrasound may provide a way to monitor storms and provide early warning of tornadoes and the like. I wonder if this is currently done.

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Physics, Astronomy & Cosmology / Re: Do far away galaxies appear to rotate slower than they are?

« on: 29/03/2017 04:51:31 »

I believe you are correct. I know of no specific attempt, however, to research the phenomenon.

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Physics, Astronomy & Cosmology / What will scenes look like if time conflicts?

« on: 20/03/2017 08:15:49 »

Suppose there exists a room, called Room A. The room has a window that is glazed in a peculiar manner: the "glass" consists of a plane such that electromagnetic radiation cannot propagate beyond it; it is 100% reflective and constitutes, for purposes of the room, a mirror. The window is actually a light switch that is reflective when "off" but transparent when "on". When "on", light can cross from the room into another room (Room B) then on the other side, and vice versa. Otherwise light is blocked both ways. Observer A in Room A with a camera sits in a chair.  T_A denotes time in Room A. At T_A = -2 seconds, Observer A gets up, walks over toward the window.   At T_A = -0.5 seconds, the window turns "on", optically connecting the rooms. At T_A = -0.003 seconds, Observer A clicks the shutter. At T_A = 0, half of the light from the flash has crossed the window into the other room.  At T_A = 0.003 seconds, the shutter closes.  At T_A = 0.5 seconds, the window switches "off".  Then Observer A goes over to a table and lays down the camera.


Meanwhile, in Room B,  Observer B in  with a camera sits in a chair.   Time in Room B will be denoted by T_B.    At T_B = -2 seconds, Observer B gets up, walks over toward the window.   At T_B = -0.5 seconds, the window turns "on", optically connecting the rooms. At T_B  = -0.003 seconds, Observer B clicks the shutter. At T_B = 0, half of the light from the flash has crossed the window into the other room.  At T_B = 0.003 seconds, the shutter closes.  At T_B = 0.5 seconds, the window switches "off".  Then Observer B goes over to a table and lays down the camera.


The rooms are both completely enclosed, and have no light sources other than the camera flashes.


Now a word about the window. Rooms A and B are in different universes, and therefore use different coordinate systems. Of particular importance here is that they do not use the same clock.  The coordinate systems ordinarily would have nothing to do with each  other; however in this case they become connected during the time when the window is "on" (this connection is how the window is turned on). Working from different universes gives us the option of flexibility in how the connection is made. Specifically, the connection is made in such a way that that T_A = -T_B.  Thus, each observer would see the other's clock running backwards.


Question:  What in general  will each observer see, and what will be the state of the photographic film in each camera at various times throughout the experiment?

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Physics, Astronomy & Cosmology / Re: How extendable is science as we know it to 4 dimensions?

« on: 11/03/2017 06:27:40 »

Trying to add a major additional dimension to string theory would, I imagine, fundamentally alter it.

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Just Chat! / Re: What should be done about the Wall street Journal?

« on: 05/03/2017 03:46:35 »

The Constitution guarantees that the press will be free. It does not guarantee that the press will be fair, balanced, accurate, or complete.  It in inherent in living in a free society that people must read widely and weigh evidence.