Posts Tagged ‘Relativity’

The Thinker

There is no Planet B

When I have time to fill in my retirement, I can easily spend it among the endless documentaries on YouTube. I have spent a lot of my free time watching videos on space-time. Space-time is the matrix in which we live and it’s very much a real thing. There is no way to separate space from time. It (not they) literally comprises the fabric of the universe, fabric that can be warped by gravitational forces. It’s fascinating stuff if you can wrap your head around it.

Some of these videos take on the topic of traveling to distant stars. They talk about why it’s prohibitively expensive in time and energy to even come close to approaching the speed of light. If we hope to escape our solar system and colonize planets around distant stars we will have to figure out how to do this. What I’ve gleaned from these videos is that there is basically no way to do this. In the embedded video, the sun is reduced to the size of pea. The videographer then shows the distance of our closest star, Proxima Centauri, which would be 125 miles away. Moreover, Proxima Centauri would be the size of a radish seed.

Proxima Centauri is about 4.25 light years away. If you could get a spacecraft to go ten percent of the speed of light, which doesn’t seem technically possible due to the energy required, it would take 42 years to get to Proxima Centauri. The chance of finding a habitable planet around it is virtually nothing, which means the closest habitable planet is likely to be much farther away. Moreover, humans hoping to emigrate there would have to bring everything they need with them. Many generations would live and die in the void of interstellar space on this journey. Given the law of entropy, it’s unlikely their vessel would make it to its destination with any of its passengers alive.

Which is why in practical terms that humans should look closer to home. Mars is probably the closest possibly habitable planet, but it really cannot be considered habitable. It has 1/100 of the earth’s atmosphere, its atmosphere is toxic and too cold for us and everything is covered in a fine dust that would probably have us looking like coal miners. We’d probably have to live underground. Most likely going there would be a one-way trip, as our muscles would likely atrophy in the lighter gravity. Pretty much everything would have to be imported from earth, at least for many decades. Just getting there would mean being exposed to high does of cosmic radiation that would change our DNA and likely mean our children would have birth defects. In short, actually living on Mars would probably be hellish. No sane person would want to stay there. Even getting there and back might kill you or at least shorten your lifespan. Perhaps we’ll find ways to shield ourselves from the cosmic radiation on the journey, but it’s unlikely.

Venus has a more earth-like gravity but is literally hotter than hell not to mention filled with an atmosphere of lethal gases and constantly swirling storms. There is some talk that maybe a moon of Jupiter or Saturn could support a human colony. Getting there would take much longer than to Mars and there is no moon that can really be considered Earth-like. Some appear to have water (ice) and something resembling an atmosphere, but life there would be problematic at best. Many of these moons seems to be rocked by earthquakes.

All this leads this space-buff to conclude that we humans are stuck here on Earth, barring some sort of incredible technology that seems extremely unlikely or some asterisks to the laws of relativity that don’t appear to exist. It’s understandable that humans will want to explore new frontiers. It’s also abundantly clear that we are quickly making the earth uninhabitable through overpopulation, pollution and deforestation.

Attempts to colonize these brave new worlds will likely prove disastrous and prohibitively costly. Yet that’s seems to be where people like Elon Musk are anxious to go. If he can shoot a Tesla toward the outer planets, a manned trip to Mars can’t be that far away. He’s hoping to do something like this in the 2020s. I confess I will be excited if he or NASA succeeds in something like this. While it is likely to be exciting, it is certainly fraught with peril. Assuming the astronauts make it back, it’s likely that their DNA will not be quite what it was. Astronauts who have spent long time periods in the International Space Station have already noted chromosomal abnormalities. Science Magazine in 2016 noted that lunar astronauts had a much higher risk of heart disease. This is likely due to the higher cosmic radiation in the space between the Earth and the Moon.

While mankind’s desire to explore other worlds is understandable, if much of our motivation for getting off-planet is to deal with the population crisis then we are being hopelessly naïve. Which means that as painful as it may appear to be, it will be infinitely less costly to address our climate, population and pollution crises here and now. Our lovely Mother Earth that we are quickly destroying is all that cocoons us.

Hopefully the Trump Administration’s foolhardy rush toward oblivion will be short-lived. Hopefully Americans will come to their senses and elect politicians that will address these problems. Resolving seemingly intractable problems like our religious and ethnic wars, or poverty or population control simply must happen or we doom humans and our ecosystem to extinction.

There is no Planet B for humans to colonize. We live on a planet that should be our Eden. We must make it that or perish.

The Thinker

Review: Interstellar

Interstellar is another one of these movies that is quite good, providing that you don’t think about it too much. Don’t let this stop you from seeing the movie if so inclined. It’s not at all a bad movie and it is quite engaging. Ignorance about science actually helps, although director Christopher Nolan got plenty of scientific help to try to make the premise semi-plausible.

The premise of the movie is that the earth is dying, at least as a habitat for sustaining human life. Not much else other than corn is growing and you will see plenty of corn, at least until Cooper (Matthew McConaughey) decides to abandon his farm and family to take a trip through a wormhole around Saturn that appears to have been placed there by an alien intelligence. The wormhole has already taken some brave cosmonauts across vast distances of space and time (actually to another galaxy) to some area of space where there are some candidate planets that might support human life. Mankind needs to vacate the earth soon, which is Cooper’s reason for volunteering to command this mission. He wants to save his daughter Murph (Mackenzie Foy) from the grisly fate of slow death that all humans will face if they don’t get off the planet soon. Apparently, colonizing Mars is out of the question.

Cooper used to be a test pilot but became just another farmer after his test flying days ended. His skills were no longer required. He’s a competent but unenthusiastic farmer who frequently wakes from nightmares from his accident as a test pilot. Fortunately, there’s a gravitational anomaly on his farm. It’s not good to have one of these, but between this and the massive dust storms that regularly arrive he and Murph are reading signs in the patterns of dust in the library of their farmhouse. And decoded it sends them to a place on their handy USGS topographic map where nothing should be. When they drive out there though they find a fenced in area. Once inside, what they really find is NASA, now a hush-hush agency, and Professor Brand (Michael Caine), the genius working on the really hard problem of moving the human race off the earth, out of the Milky Way and to some far flung place to ensure the survival of the species.

This sounds like a worthwhile endeavor but goodness, what a strange set of coincidences already because Cooper already knows Professor Brand from his flying days. Brand immediately petitions him to take a spacecraft to Saturn, because he is the best test pilot he ever saw. He wants Cooper to take it through the wormhole and then to various systems and planets abnormally affected by gravitational waves to find a planet that humans can colonize. Just in case no one on earth can actually follow them en masse, each spacecraft comes complete with human incubators to restart the species on a suitable planet. It is, to say the least, a series of remarkable coincidences. But it’s just the beginning of these as well of many questions.

For me, among the questions is why some sort of intelligent species would place this prominent and useful wormhole near Saturn but not bother to give them a way to communicate. Then there is the physics on whether you could actually traverse through a wormhole and survive on the other side. Obviously, it makes for a great movie if you can. After a long trip from Earth to Saturn with his two travelling companions Brand (the professor’s daughter, played by Anne Hathaway) and Romilly (David Gyasi), they do slip through the wormhole. Cooper and Brand quickly engage in a series of literally hair-raising visits to a couple of local planetary systems. They go there to find some pioneers who went there and to see if the planets are habitable. Gravitational waves and relativity play major tricks on them, allowing them to age hardly at all while Romilly waits 23 years for their return. Meanwhile, Cooper knows that back home his daughter Murph is aging relatively much more quickly than he is and is seriously wacked out by her father’s disappearance. He promised to come home and get her, but as decades pass it’s hard to see how this can happen, particularly when none of the previous explorers have come back. Fortunately, at least one-way communications from Earth is possible. This gives Cooper many opportunities to tear up when he gets sporadic reports from Murph, who quickly catches up with him in age.

So yes, the plot is a bit convoluted and incredulous at times, but it is all portrayed quite realistically otherwise. Most science fiction and space operas don’t talk about the problem of relativity. At least this one tackles it. And the acting is quite good all around. The acting includes a supporting role for Matt Damon, who plays one of the pioneer astronauts, Dr. Mann.

The plot frequently moves across space and time, to this far-flung galaxy then back to earth, NASA and Dr. Brand’s lab where little Murph becomes one of his scientists and helps him with his complex space/time formula he can’t quite seem to finish. There are plenty of suspenseful parts of the movie. If you are having trouble feeling affected by the acting, then you can revel in the voluminous orchestration that, if you are of a certain age will sound familiar. It’s not just the organ music that feels like it’s come out of 2001: A Space Odyssey, but many of the characters as well as much of its plot. Yes, the movie feels like it is something of a homage to the classic 1968 science fiction movie, imitating it in many ways but fortunately not in 2001’s cerebral nature, divorced as it was from emotion.

Matthew McConaughey has grown up as an actor. In the past I have panned his movies. Here he gets to play a serious role rather than a pretty boy with flaxen, blow dried hair, and he does a good job with it, as does Anne Hathaway, of course as his female partner Brand. There is plenty of emotion to revel in too, which considering the weighty topic of the survival of our species seems quite appropriate.

Just don’t think about it too much. Don’t think about how they manage to survive such a long time (hibernation certainly helps) in their spacecraft, don’t think about the improbability of emerging alive on the other side of a wormhole, and don’t think about the likely lethal amounts of cosmic rays just a trip to Saturn would have given them. Presumably NASA figured out a workaround. As regular readers may remember, I don’t believe we are destined to live on other planets, let alone other solar systems or galaxies, given the daunting nature of known physics and the distances between solar systems. Earth is it for our species, I’m afraid. But if you have to dream about such a possibility, Interstellar gives you as plausible a scenario as you are likely to get. It’s just, if you have studied the science and do think about it, you realize it is still implausible.

But you probably won’t care too much. Overall the movie is too good not to ignore a lot of dubious science and major issues with the plot in general. Indulge and enjoy. Here’s one movie that is quite literally stellar.

3.3 points on my four-point scale.

Rating: ★★★¼ 

The Thinker

Mankind is not going to the stars

I’m something of a space geek. It helps to have grown up during the space race. I still find the exploration of outer space fascinating. Our knowledge of the universe is growing by leaps and bounds. Hundreds of planets have been discovered, so many that it no longer makes news to announce new ones. Many of these planets look like they might support human life, although it’s hard to say from such a fantastic distance away. Some of us are waiting expectantly for someone to discover the warp drive, so we can go visit and colonize these distant worlds. Maybe it will be just like Star Trek!

It fires my imagination too and it excites the popular press as well. It all sounds so exotic, fascinating and Buck Roger-ish. The only problem is that almost certainly none of this will happen. We might be able to put men on Mars, but colonizing the planet looks quite iffy. Even colonizing the moon, as I suggested when Newt Gingrich was promoting the idea during his last presidential campaign, is probably cost prohibitive. Which means we need to keep our dreams of visiting strange new worlds in check. It won’t be us, it won’t be our children or grandchildren and it probably won’t happen at all. To the extent we visit them it will occur virtually, using space probes.

I don’t like to be the bearer of bad news but hear me out. We probably won’t colonize the moon permanently because it will be too costly to sustain it. It’s one thing to land a man on the moon, which America did rather successfully. It’s much more costly to stay there. For a sizeable group of humans, say ten thousand or so, to live self sufficiently on the moon is probably impossible. If it can be done it will take a capital investment in the trillions of dollars. My guess is that it would take tens of trillions of dollars, if not hundreds of trillions of dollars. It’s unlikely the moon has enough water that we could mine but if it does it’s likely very inefficient to process as it is wrapped up in moon dust. Otherwise water would have to be imported from earth at ruinous costs. In fact, colonists would have to import pretty much everything. Even if citizens of the moon could grow their own food and recycle their own water, manufacturing is likely to be limited. We might have a small scientific colony on the moon, like we do at the International Space Station. It probably won’t amount to more than a dozen men or women, and it’s likely to cost at least ten times as much as the international space station cost, since you have to move equipment and men a much further distance.

What about man colonizing Mars? It doesn’t seem out of reach. When the orbits are working just right, a spacecraft can transit each way in about six months. The cost of getting a pound of matter to Mars is likely ten to a hundred times the cost of getting it to the moon, which is probably cost prohibitive in itself. The journey there and back though looks chancy. It’s not just the possibility that some critical system will fail on the long journey; it’s the cosmic rays. Our astronauts are going to absorb a heap of radiation, the equivalent of 10,000 chest X-rays. It looks though that this is probably manageable. What of man living on Mars itself?

The good news is that humans could live on Mars, providing they don’t mind living underground. The atmosphere is much thinner than Earth’s, it is much colder on Mars than on the Earth in general and you can’t breathe the air and live. It’s true that by essentially burying our houses in Martian soil humans could be safe from much of it. Slapping on some SPF-50 sunscreen though won’t do the job. Anyone on the surface will have to wear spacesuits. So far we haven’t found a reliable source of water on Mars either. Colonizing Mars is within the realm of probability, but it is fairly low. Frankly, it’s a very remote, cold and arid place with nothing compelling to it other than a lot of empty mountains and valleys and swirling Martian dust, almost always in a pink or orange haze.

Colonizing distant moons and asteroids have similar problems: no suitable conditions for sustaining life as we know it, insufficient gravity, toxic radiation, frequently toxic chemicals and cold of the sort that most of us simply cannot comprehend it. Both Venus and Mercury are simply too hot to inhabit, and Venus is probably as close to hell as you will find on a planet in our solar system.

What about colonizing planets around other solar systems? Here’s where we need to fire up the warp drive of our imaginations because as much as physicists try to find exceptions around Einstein’s theories of relativity, they can’t. The closer you get to the speed of light the more energy it takes. It’s like Sisyphus pushing that rock up the mountain. To get a spacecraft with people in it to even 10% of the speed of light looks impossible with any technology we have or can reasonably infer. The closest star is three light years away, so even if this speed could be achieved it would take thirty years to get to the closest star. But it can’t be achieved. In fact, we’d be lucky to get to 1% of the speed of light, which would make a journey to Proxima Centauri a voyage of 300 years. Moreover, if some generations could make the journey, it is likely that our closest star is not inhabitable.

Perhaps we could freeze ourselves and wake up millions of years later at our destination. Maybe that would work. Obviously, we don’t have technology to do anything like this now. And given the laws of entropy, it’s hard to imagine any spacecraft that could survive a voyage of that duration intact.

What we need is a warp drive and a starship. But what we will really need is an escape clause from the theories of relativity and the technology that will allow humans to utilize it: a spacecraft that can slip through a wormhole or something. It’s not that this is impossible, but with what we know it looks impossible for us and will always be impossible. In any event there doesn’t appear to be any wormholes conveniently near Earth.

In short, we are stuck to the planet Earth. We’d best enjoy what we have and stop squandering the planet on which all human life depends. So far we are doing a terrible job of it.


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