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420chan is Getting Overhauled - Changelog/Bug Report/Request Thread (Updated July 10)
Sagittarius Dwarf Galaxy: Home? Ignore Report View Thread Reply
Arthur Eddington - Fri, 19 Oct 2018 18:25:45 EST ID:457vC2+I No.57470
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>>original article
http://viewzone.com/milkyway.html
>>rebuttal
http://blogs.discovermagazine.com/badastronomy/2007/06/27/is-the-sun-from-another-galaxy/#.W8pUPmhKiUk

Quick rundown of the findings, which are earth-shattering if fully true, and still quite interesting if only partially true: our galaxy is orbited by a smaller spheroidal dwarf galaxy currently visible within the constellation Sagittarius. For hundreds of millions of years, it has been orbiting in a perpendicular orbit after having been pulled into the Milky Way's gravity, having stars pulled off of it each time it passes through the galactic disk, to the point now where it is very small, faint, and nearly at the point of losing gravitational cohesion. You can see a visualization of the stream of radiation left by the galaxy astronomers used to determine its path in the pic.

Now this is where it gets interesting.

It just so happens that Sol is directly within this stream of debris. For 99.9% of our orbit around the galaxy, we wouldn't be within that stream. Also, incidentally, we are at an angle to the plane of the galaxy, which was always thought a little bit odd, since most stars planetary orbital plane is parallel to the galactic plane since during accretion their accretion disks are subject to inertial forces from the star's orbit around the galaxy.

Given the extreme odds of us just happening to be within that stream, it would seem to suggest that Sol itself is native to the dwarf, having been pulled out on the dwarf's last passage through the galactic plane.

Implications:
-The period of the dwarf's orbit is around 200 million years. It is roughly 25% of the way through its orbit counting from our position in the galactic plane, which means we would have been caught by the Milky Way about 50 million years ago. The last time we passed through the plane before that, presumably still gravitationally bound to the dwarf, would have been 150 million years ago.
-Incidentally, these numbers roughly coincide with major extinction events on earth, presumably because the gravitational disruption of passing through the galactic plane would disturb the Oort cloud and send high levels of asteroids into the inner system.
-If this is true, the Drake equation is completely bunk, since we have assumed that earth was native to the Milky Way in making our estimates about life.
-Radiation levels in the dwarf are much, much lower than in the Milky Way. If this true, that means life developed on our planet under a condition of much lower radiation than we are currently experiencing. I don't need to tell you life and radiation don't get along, so this is a startling finding about the long-term future of life on earth (and indeed in the galaxy at large) if true.
-Higher galactic radiation would increase mean solar radiation, increasing damage to DNA among other effects. This could explain the sudden rise of mammals, as their more robust homeostatic systems could perhaps better deal with the heat increase. This would also explain why all the planets in the solar system -- not just earth -- are experiencing climatic shifts in a hotter direction before you get your panties in a bunch, we're talking about a period of warming that has been going on for at least 50 million+ years. It can't be used to explain anthropogenic climate change, which is still real

Problems:
-While I don't find the rebuttal wholly convincing (its argument about the plane of the solar system is misleading at best, as well as its argument about where we should find ourselves relative to the ring of debris -- at the very least, it's not the slam-dunk debunk the author tries to pretend it is) it does bring up the problem of the lower general metallicity of the dwarf galaxy's stars. However, we can't really estimate what the stellar population of the dwarf was when it first arrived, since so many stars have already been stripped off, so this doesn't tell us as much as you would think.

What are your thoughts /sagan/? Big if true, fascinating if false, or a bunch a bunk?
23 posts and 6 images omitted. Click View Thread to read.
>>
Edwin Hubble - Sun, 24 Feb 2019 05:52:39 EST ID:U4u72hWB No.57541 Ignore Report Reply
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>>57470
uneducated pleb here. would it be a good idea to strive for escaping back to the drawf galaxy assuming out system came from there? If this galaxy has higher radiation than that dwarf galaxy which supposedly we evolved from. 150 million years or so i the estimate for the transit that's with in our line of evolution isn't it? Then should we worry about an inevitable dead end in ou evolution or would we acclimate? Maybe escaping this galaxy would be a good idea esp if the fermi paradox is thrown right out the window giving the conditions here, who knows what the fuck lives here. But I'm more interested in our basic survival odds, not counting for the clockwork mass destruction events.

This some sci fi shit my dudes.
>>
Bernard Burke - Mon, 25 Feb 2019 19:19:08 EST ID:457vC2+I No.57542 Ignore Report Reply
>>57541
These are all unknowns, however the suggestion I made in OP was that mammals kind of are life's 'adaptation' to the current environment. But I mean, if we're going to survive in the galaxy long term, being biological organisms prone to radiation makes us vulnerable in lots of other ways too. So it's best just to fix that.
Besides, the level of tech we would need to migrate to the dwarf is way higher than the level of tech we (or any other aliens) would need to become machines, so if this galaxy is indeed fatal to organic life, most civilizations would converge on that as the optimal solution I think.
>>
Johann Bode - Sat, 16 Mar 2019 20:38:40 EST ID:rNBxnMOH No.57573 Ignore Report Reply
>>57541
OP's post sounds like a bunch of absolute hogwash and I cannot find any other sources for it than his own link which literally discusses things like bigfoot alongside this.
>Then should we worry about an inevitable dead end in ou evolution or would we acclimate?
No because we are currently living in a man made mass extinction event already caused in part but not entirely by climate change (the rest of the mass extinction is due to numerous other factors of human activity like 7 billion hungry mouths stripping the ocean of all sea life, completely eradicating entire species by hunting them to extinction like the Wooly Mammoth, and numerous factors from our reckless massively polluting and sharply expanding urban civilization). The amount of destruction on a global scale reminds me of a bacterial sheet. The human organism became out of whack and overcolonized its own petri dish. I think the current stage in humanity is ample evidence that intelligent technological civilizations are unlikely to ever be found because in the few instances where it happened it likely destroyed itself either wiping out the civilization or outright sterilizing much of the planet, and that is assuming these societies didn't do something really stupid like knock themselves out of orbit careening into the sun, creating a massive enough singularity to swallow their planet whole before evaporating, or any number of other scenarios in which case the actual planet itself no longer exists.

But as for now, what happens in millions of years is pretty fucking irrelevant to us when we're talking about things like climate change moving us towards ecological and societal collapse within the next hundred or two hundred years.


No flat earth thread? Ignore Report View Thread Reply
Jessica Tandy needs candy !!vVWR8L52 - Mon, 29 Oct 2018 19:21:02 EST ID:F2wgR3l2 No.57479
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And before you ask /tinfoil/ is currently in the middle of forum sliding and if this it's treated as a serious topic then that's like saying climate to deniers are right

https://m.youtube.com/watch?v=e5ACN9iF8Jw
https://m.youtube.com/watch?v=qkRnJutL5ko
https://m.youtube.com/watch?v=CGjFAe018oA

I have included counter arguments so that people can reach their own conclusions, it's hard to go against the grain and try to prove a point therefore

>It certainly is interesting to see the shift of focus in space programs from official government organisations to privately-run organisations. Whether or not that's a good thing will, of course, vary with your political views, but the ultimate outcome isn't much different. After all, corporations are driven by profit, not the pursuit of knowledge or truth.
>What is surprising, however, is the new generation of people shouting "It's true, I saw it on TV!" Except this time, it's the Internet. We have already witnessed the shortfalls of this blind belief in online materials; just consider recent US elections, the political Facebook campaigns in the UK, or the many fake-news sites run from countries like Macedonia.

In the days of Newton and Hailey there weren't dogmatic schools that tried to systemize learning. People were free to experiment and come up with theories, look at Faraday, the father of electricity. He was smart even though he didn't have a degree.

Basically universities are what the Catholic Church was back then (let's grow up no alter boy jokes please) in that they are dogmatic and have a reason to protect their source of money and funding.

I mean why was the Bush administration so keen on going to mars?
5 posts omitted. Click View Thread to read.
>>
Michael - Thu, 06 Dec 2018 23:38:20 EST ID:Q1CtxL06 No.57530 Ignore Report Reply
>>57514
apostrophes are an Illuminati conspiracy, get woke fool
>>
Georges-Henri Lemaitre - Fri, 07 Dec 2018 16:17:18 EST ID:fA4CdeQA No.57532 Ignore Report Reply
>>57508

TRUTH! Have you ever seen the moon except in pictures? That's because it's all edited in by nasa. Aliens implanted false memories of seeing the moon. It's all a big conspiracy to keep the human race ignorant and in line.
>>
Jessica Tandy needs candy !!vVWR8L52 - Tue, 11 Dec 2018 22:55:57 EST ID:wlUjYsjb No.57538 Ignore Report Reply
No ones proved me wrong yet!

Wo wo we!

I recently thought why couldn't Earth be like an Age of Empires II map?


How did such an inconceivably awesome object get stuck with such a stupid name? Ignore Report View Thread Reply
Henrietta Levitt - Thu, 18 Oct 2018 20:49:56 EST ID:gVSzJCUs No.57466
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"Milky Way" sounds so weak and lame for a galaxy, especially the one we're renting. Cant we have come up with a cooler handle for our cosmic digs?
7 posts and 2 images omitted. Click View Thread to read.
>>
Christiaan Huygens - Mon, 03 Dec 2018 11:34:34 EST ID:gRsMKZUR No.57520 Ignore Report Reply
>>57516
there are dark zones around. probably some near where you live. or get a look at the sky on a nighttime flight, it's pretty awesome above most of the atmosphere
>>
Johannes Kepler - Mon, 03 Dec 2018 20:45:06 EST ID:457vC2+I No.57523 Ignore Report Reply
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>>57520
Stars, y'say? Heard there's a mighty fine mess of 'em iffen ya know whar to look. Use this here map and prospect yerself a dark zone, pardners:
https://darksitefinder.com/maps/world.html#4/36.39/22.15
>>
Riccardo Giacconi - Wed, 05 Dec 2018 10:01:26 EST ID:IpCFcmN3 No.57526 Ignore Report Reply
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>>57519
that kind of a technical answer i needed, thanks. sorry for being a clueless plebian.


Mars eclipse Ignore Report View Thread Reply
William Huggins - Sun, 25 Nov 2018 21:39:22 EST ID:ckw062Hz No.57504
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if one or 2 of mars moons came between mars and earth during a time where mars is clearest and easiest to see with the naked eye, could one tell the moons were dimming mars red orange light? I understand phobos is really close but could the other moon make a significant enough eclipse or dimming effect to the red dot we see from earth
>>
Fred Hoyle - Mon, 26 Nov 2018 17:36:55 EST ID:457vC2+I No.57505 Ignore Report Reply
Naw, not with the naked eye. Phobos, the larger moon, is only 27 km across.


Perseid meteor shower! Ignore Report View Thread Reply
Johann Encke - Wed, 31 Jul 2013 11:29:34 EST ID:evrPe8Vs No.51233
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AWWWW YEAAAH.
Anyone else gonna observe this beautiful event?


Incase you haven't heard from AUG 12th to the 13th between 10:30PM and 4:30 AM, The sky's gonna light up with massive fireballs brighter than Jupiter.
43 posts and 7 images omitted. Click View Thread to read.
>>
Christiaan Huygens - Sun, 19 Aug 2018 18:20:31 EST ID:457vC2+I No.57435 Ignore Report Reply
>>57000
Almost all meteor showers are annual or cyclical, dood. We aren't here to teach you astronomy, we're here to talk about it.
>>
Roger Penrose - Tue, 09 Oct 2018 05:59:14 EST ID:U4u72hWB No.57464 Ignore Report Reply
>>57000
if you don't ask they don't have time to tell.
>>
Wilhelm Beer - Thu, 15 Nov 2018 04:28:30 EST ID:N7xCPuZj No.57491 Ignore Report Reply
Leonid shower's s'pposed to be coming up this weekend, for those who won't have a big honkin' snowstorm gumming up the skies, at least.


/STEM/ Ignore Report View Thread Reply
Arthur Eddington - Thu, 01 Nov 2018 23:18:58 EST ID:7ez/W0kB No.57485
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Slow board, maybe we should have /stem/
>>>/420/247062
>>
Subramanyan Chandrasekhar - Fri, 02 Nov 2018 03:15:02 EST ID:m8u2eXUq No.57486 Ignore Report Reply
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>>57485
Everyone is planning a space party lately



Maybe they need more time to planet.


duuuuuude Ignore Report View Thread Reply
Galileo Galilei - Thu, 01 Nov 2018 22:59:06 EST ID:6fcUdTGI No.57484
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https://www.eso.org/public/news/eso1835/
see that spherical black shit under the gas? that the event horizon. not actually a thing but a region where even light falls in. that bubble isn't even contorned by gas but the gas's glow stretches in a sphere because of gravity tides.
this shit is awesome that's what it is


Dark Matter and GR - struggling to understand Ignore Report View Thread Reply
Bart Bok - Sun, 30 Sep 2018 09:15:14 EST ID:9RKOIT3O No.57458
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Hey there fellow egghead stoners. Would you be able to guide me through this?

So, the whole concept of dark matter and energy. I find it a little dubious, I take it this hasn't been confirmed in any way - rather, like many theories in physics has been introduced as an attempted explanation of mismatch between empirical data and theoretical predictions.

But this is just an impression I've got from the superficial knowledge of modern physics I've got, so I'd rather first understand the basis for this hypothesis better before judging it dubious.

So the way I understand it is the concept was proposed in 30s to explain the observed movement of galaxies, in particular why some stay in clusters rather than be launched off due to the acquired speed.

So it is inferred that there must be enough gravity force to keep them together instead. This begs the first question: what is the expected mass calculation based on? As in, how'd they go about measuring that?

But all right, aside from that bit I'm missing, assume the mass predictions are sound. In Newtonian mechanics - so far so good. But now if we introduce GR we allow the concept of black holes which would escape our observations. Why does that not account for 'dark matter' effect? It fits the criteria of (1) great mass (2) inability to be observed

So the way this is taken into account, I understand, that all right - there may be black holes which we cannot observe, but we still have a rough prediction on their mass which we infer from gravitational lensing - and that is way not enough to account for 'dark matter', and hence the concept remains valid.

My questions to you anons:
1) Is the line of reasoning above more or less sound
2) Any resources on the subject to recommend which would explain in bit more detail how the calculations made? (seems like internet is full of pseudoscience articles but I can't seem to easily google a decent source)
3) Could it be possible that inferring
i) mass bends spacetime
ii) spacetime is observed to be bent
iii) therefore there must be mass
is wrong, because mass may not be the only reason the spacetime is bent. That is, could it be that the 'dark matter effect' is not due to some exotic type of matter, but rather an innate (or otherwise not yet understood by our science) geometrical feature of spacetime.
>>
Johann Encke - Mon, 01 Oct 2018 01:21:26 EST ID:457vC2+I No.57461 Ignore Report Reply
>> what is the expected mass calculation based on?
Light from main sequence stars. We look at a galaxy, look at it's luminosity to estimate the number of main sequence stars, and estimate mass from that. Almost all galaxies thus have a totally insufficient amount of normal matter to account for their mass (although we have found some galaxies without dark matter, or with hardly anything but dark matter, but this is quite rare) or rather, what their mass would have to be in order for them to maintain coherency.

>> there may be black holes which we cannot observe, but we still have a rough prediction on their mass which we infer from gravitational lensing
You would think we could do this, but in practice we can only use gravitational lensing and other gravitational effects to detect black holes in this way if there is a significant amount of parallax on the black hole (otherwise, unless we are just lucky enough to have a sufficiently bright star in line with it and us along its event horizon, we will simply miss it) for this reason we can use this method to kind of hunt randomly for black holes, we can't use it to estimate how many black holes there actually are -- we have no idea as to the answer to that question, from an empirical standpoint.
>>2) Any resources on the subject to recommend which would explain in bit more detail how the calculations made?
https://ned.ipac.caltech.edu/level5/March05/Read/Read1.html
>>iii) therefore there must be mass
I think there are strong reasons to suspect this line of thinking might be flawed, especially since the only reason we describe dark matter as matter is simply because we can't think of anything else to describe it as. Relatively popular but unaccepted are theories that dark matter and energy represent the influence of alternate quantum realities upon our universe, or may otherwise be some sort of shadow of the m-brane. Unfortunately, a long running contender for non-DM/DE explanations, MOND, was recently disqualified due to new observations, although people are seeing if it can be saved with an update.

In short, absolutely it could be something else. DM/DE really is just a placeholder. But that begs the question: what else? We've been scratching our heads on that one for almost a hundred years, and we have uncovered startlingly little.
>>
Fred Hoyle - Sat, 06 Oct 2018 19:23:55 EST ID:8/fKg+Ea No.57462 Ignore Report Reply
>>57461

Hopefully the James Webb space telescope will be launching under it's most recent date in 2021 and provide us some new insights.


That FTL means time travel meme Ignore Report View Thread Reply
Pierre-Simon Laplace - Sat, 16 Dec 2017 22:22:45 EST ID:hGyQlc1t No.57130
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I have a question regarding this:
If you look at this gif it shows you "backwards" travel:
The first "jump" after the first acceleration points into the direction that corresponds to the lower left quadrant of the previous reference frame leading to backwards time travel.
However: Drawing it into the upper right quadrant should be equally legal which would imply forward time travel. This would imply that direction you are moving in space would dictate the direction of the "time travel" which seems entirely non-sensical to me.
I guess this is also the point but I still get the feeling I'm missing something here.
20 posts and 3 images omitted. Click View Thread to read.
>>
Bernard-Ferdinand Lyot - Thu, 27 Sep 2018 18:55:44 EST ID:3nlPOKZc No.57456 Ignore Report Reply
>>57130
>>
Bart Bok - Sun, 30 Sep 2018 09:42:04 EST ID:9RKOIT3O No.57459 Ignore Report Reply
>>57130
>However: Drawing it into the upper right quadrant should be equally legal
Equally illegal? ;)

>This would imply that direction you are moving in space would dictate the direction of the "time travel" which seems entirely non-sensical to me.
These diagrams are entirely symmetrical in terms of all dimensions, as in choice of 'left' and 'right' just as 'up' and 'down' is arbitrary

I feel there is an ambiguity in what constitutes time travel. As in, the intuition we typically may have about this being '2018-09-30' -> '2008-09-30' same place.

But in terms of general relativity, any travel with speed >c is time travel. This is called moving in a 'timelike curve' in 4D spacetime - as opposed to 'spacelike curves' which we (and all we know) typically move on. On the GIF all curves within yellow area are spacelike and blue area timelike.

So for example if you 'teleported' a light year away from your current whereabouts, that'd be considered time travel. Because if you send a light signal to earth, and teleport back - you will not see it for another year. So you influenced the future without exactly 'changing' the date on your calendar

Mind you if you simply travel half a year back/forward keeping your position fixed, you'd arrive in some different place because likely the earth, sun and entire galaxy would've moved away.
>>
Bart Bok - Sun, 30 Sep 2018 09:55:02 EST ID:9RKOIT3O No.57460 Ignore Report Reply
or maybe better example:
  1. you travel a year back in time from now to 2017
  2. you end up a light year away from initial position
  3. 2017 you wants to send stock market results to 2018 you
  4. at best 2017 you will be able to send them with speed of light
  5. light takes a year to arrive to 2018
  6. in that case, the information you're sending arrives in 2018 and you haven't actually managed to send it back in time, because it still has to make up for the distance before it reaches you

if you change space distance from 1 light year away to 0.5 light year away however, you will be able to send information to 'past you' (with speed of light) so it arrives mid-2017 (and either you're filthy rich or paradoxically disappear hehehe)


Interchan Warning System Ignore Report View Thread Reply
Maximilian Wolf - Fri, 28 Sep 2018 00:48:46 EST ID:9ugkcJUP No.57457
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***THIS IS THE INTERCHAN WARNING SYSTEM***
THIS IS NOT A TEST
MESSAGE TO FOLLOW
MESSAGE FOLLOWS:

DO NOT SHIFT THE TIMELINE. DO NOT LISTEN TO 'AI' BASED POSTS.
DO NOT SHIFT TO TIMELINE: 5E8FD0AA-44ED-4868-B04C-9E33754CF9BC
DO NOT DESPAIR

***End of message***
>>
Bernhard Schmidt - Thu, 15 Nov 2018 20:29:27 EST ID:rNBxnMOH No.57496 Ignore Report Reply
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All weebs should be shot nb


fate of universe Ignore Report View Thread Reply
Jocelyn Bell - Sun, 14 Sep 2014 23:31:05 EST ID:SknUZfy5 No.54393
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Is there a theory that says that eventually the universe will expand so large that it will collapse in on itself and create another big bang?

What are your thoughts on the fate of the universe?

"The Last Question" by Isaac Asimov is a short story about the fate of mankind and the universe. Idk if everyone on this has read it or not, but I love it. Here's the link: http://www.multivax.com/last_question.html
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Charles Messier - Tue, 04 Sep 2018 11:45:13 EST ID:457vC2+I No.57444 Ignore Report Reply
>>57443
I'll help Lemaitre out by saying the first two statements are uncontroversial possibilities thoroughly discussed ITT. The first is the Big Freeze, Heat Death, leading to a Big Rip: https://en.wikipedia.org/wiki/Big_Rip
The second is the Big Crunch, which is now thought to be impossible under current observations but was popular in the 20th C.: https://en.wikipedia.org/wiki/Big_Crunch

As for the third I have no idea what he's alluding to and I'm really interested also.
>>
Johannes Kepler - Sat, 22 Sep 2018 19:46:39 EST ID:kahFeNFq No.57452 Ignore Report Reply
>>57442
>Woah what? Who thinks that?
people trying to unify quantum mechanics and general relativity into a single theory

do you try to quantize gravity or do you try to gravitize quanta?
do you treat quantum entanglement as tiny wormhole?
do you treat blackhole as the entropy surface?
could geometry of space be determined by level of entanglement in quantum foam in a region of space?
could dimensionality of space be an emergent property of quantum mechanics?

>I know relating the the dimensions of space is that one that suggested that 3 dimensions of space and 1 of time was the only logically possible one, that all other kinds of universes would be literally impossible. I don't agree with that idea but it seems like people have given up on making a rigorous theory of the relationship between the dimensions (or assume GR's spacetime covers it.)

try incorporate probabilities into dimensions of space

does the "literally impossible" part come from encountering infinity and divide by zero with utilizing earlier understanding of mathematics?
>>
Chushiro Hayashi - Sun, 23 Sep 2018 00:01:29 EST ID:457vC2+I No.57453 Ignore Report Reply
>>57452
>>does the "literally impossible" part come from encountering infinity and divide by zero with utilizing earlier understanding of mathematics?
Perhaps, it is more like the image suggests; it's a suggestion about the topology of spacetime and whether causality or space could be consistent with that number of dimensions. However, it's equally likely that all those other possible coordinates could also have universes like ours, in which the mathematics equally suggest that only their dimensional composition is possible and all others impossible.


How does a closed Ignore Report View Thread Reply
jolinar - Mon, 16 Jul 2018 20:31:55 EST ID:4+cG6NBX No.57348
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Timeline curve work? Could you be trapped in it forever ?
I have a writing prompt
>>
Stephen Hawking - Tue, 17 Jul 2018 00:04:28 EST ID:457vC2+I No.57349 Ignore Report Reply
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Closed timelike curves are totally theoretical objects -- we have no real information about how they would work, or if they are even possible. Essentially, what is 'curved' in a CTC is the 'geodesic' of spacetime. What this means that, for example, if you had a geodesic curvature in space at a 45 degree angle and you fired a laser beam into that space, as it entered it the beam within it would appear to you (if you could see it reflected) as if it had bent at that same angle even though it encountered no object. In a 'closed' timelike curve, remembering that space and time are a continuum, if the curvature is so extreme that it forms a torus, i.e. loops back on itself, and one traversed the distortion in the (normally flat i.e. euclidean) curved spacetime, one could end up at the end of passing through the distortion at the same point in space, but an earlier point in time.

If you were stuck on it would depend on how you got into such an unusual object in the first place. If the geodesic torus could only be made so small, so that in order to traverse it one had to travel at relativistic speeds, the degree of time distortion could be amplified. Also, it's possible that actual matter (rather than energy) trapped within a CTC could become inertially unbound, so there might be no way to stop a spacecraft (for example) that was travelling through one, trapping its crew on an eternal voyage into the past (or future, depending on the 'direction' the geodesic is distorted in the fourth dimension.)

Anyway, a lot of people will not see any time travel story as 'hard sci-fi' so you probably have a lot of leeway. Hawking famously believed that a CTC would destroy itself in a cosmological version of the grandfather paradox, as heat from the torus' relative future would propagate backwards in time, eventually creating a thermal singularity that would destroy it.
>>
Vesto Slipher - Thu, 13 Sep 2018 15:52:54 EST ID:BJSneKKV No.57445 Ignore Report Reply
>>57348
I’ve seen it trapped forever
>>
Annie Cannon - Sat, 15 Sep 2018 13:46:07 EST ID:yzfSDg8q No.57446 Ignore Report Reply
Theoretically, you cease to exist in the timestream as soon as you get in the box, while your time-travelling double (who left the box at some point in the past) continues along the timestream as normal and never gets back in the box. In theory.


moon Ignore Report View Thread Reply
Jocelyn Bell - Thu, 31 May 2018 10:35:24 EST ID:HhkM3rED No.57285
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Does the moon really have influence on behavior? Or is it a well loved myth?
13 posts and 4 images omitted. Click View Thread to read.
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Stephen Hawking - Tue, 17 Jul 2018 00:22:10 EST ID:457vC2+I No.57350 Ignore Report Reply
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>>57346
I think I'll play it safe and leave it at that for here. Took the meta topic (of skeptical illuminism) to /spooky/ like you suggested, to expand it a bit beyond simply astrology. See ya there anyone who is still interested!
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Jericho !.iRAtomic2 - Wed, 22 Aug 2018 00:13:41 EST ID:qgHixtEA No.57436 Report Reply
>>57285
So, as a general skeptic of anything that can't be scientifically proven, I never actually believed in this.

Until I started working with people with developmental disabilities.

For whatever reason, the day after full moons, behaviors in clients would spike drastically. Most of the times that I was attacked, bitten, had my hair pulled, was the first day after a full moon. My personal belief was that this may simply be a function of the increased amount of light at night, with my reasoning being that it kept people up more at night, especially those who were sensory sensitive. As irritability is a common side effect of lack of sleep, this would lead to clients being more sensitive to stimuli that might upset them. Obviously, this is all anecdotal, but I think it deserves to be said. I actually have data on attacks and behaviors from one client who required close recordkeeping, but have yet to compare this data to full moons. However, I do know that at least a few times, the night was completely overcast. Perhaps enough light filters through the clouds to support my theory of light interfering with sleep, but I really couldn't say without having actually measured the amount of moonlight on a nightly basis. And if it was solely a question of light, why didn't these behaviors occur in a smooth curve as the moon waxed and waned, instead of tending to occur all at once, the day after the full moon?

I really don't know. I wish I had answers, because it would have helped me out a lot in my last job.
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Edmond Halley - Wed, 22 Aug 2018 15:08:12 EST ID:457vC2+I No.57437 Ignore Report Reply
>>57436
How could it really be the light though, since humans have been exposed to a huge amount of additional light thanks to artificial lighting and no one has gone crazy? There would have to be something special about light coming from the moon, which is even a more woo-woo direction to go in that assuming it has something to do with the tides or magnetism.


Lakes of liquid water found on Mars Ignore Report View Thread Reply
Caroline Herschel - Thu, 26 Jul 2018 15:44:03 EST ID:CZNpyEE2 No.57358
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Ground-penetrating radar images of the southern polar cap of Mars taken by ESA's Mars Express suggest the presence of liquid water 1.5 km beneath the surface. As pure liquid water probably cannot exist at such a shallow depth and low temperature, the research team posits that the water is a brine with salts and perchlorates that dramatically lower its freezing point. The largest discovered aquifer is 20 km wide, but its thickness cannot be accurately estimated. The water reservoirs would take the form of salty brine pools beneath the mile of layered ice and dust, or the water might be a component of thicker brine-dirt sludge, mixed with Martian regolith.

http://www.sciencemag.org/news/2018/07/liquid-water-spied-deep-below-polar-ice-cap-mars
http://science.sciencemag.org/content/early/2018/07/24/science.aar7268


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