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420chan is Getting Overhauled - Changelog/Bug Report/Request Thread (Updated July 26)

Black hole sun Won't you come And wash away the rain Black hole sun Won't you come Won't you come

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- Wed, 10 Apr 2019 10:40:58 EST eygzYfFg No.57629
File: 1554907258327.jpg -(66184B / 64.63KB, 1600x900) Thumbnail displayed, click image for full size. Black hole sun Won't you come And wash away the rain Black hole sun Won't you come Won't you come
These absolutely crazy mofos did it.


They took a picture of the universe's asshole. WTF mate, the amount of data they had to collect is just mindboggling.
24 posts and 4 images omitted. Click View Thread to read.
Nicolaus Copernicus - Thu, 09 May 2019 04:08:03 EST PkLJZC5m No.57688 Reply
Maybe because it isn't saturn and it's 50 million light years away?
Tadashi Nakajima - Thu, 09 May 2019 16:55:29 EST kZncG2o1 No.57691 Reply
Don’t use such big numbers I still get scared from getting too emotional

Space is genuinely terrifying and I love it.

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- Tue, 05 Mar 2019 08:35:50 EST CxvjOUYt No.57550
File: 1551792950052.jpg -(112303B / 109.67KB, 900x666) Thumbnail displayed, click image for full size. Space is genuinely terrifying and I love it.
I was listening to an episode of "The last podcast on the left". They were talking about the WOW signal.
If you aren't familiar LPOTL is a bit like coast to coast AM but hosted by some guys who are actual skeptics and fun. So some of this may not be accurate but its fun to think about.

They were saying that if it was anything intelligent broadcasting that we only got a snippit of the message because at the time scans of the sky were limited to rotation of the earth (they used the number 72 seconds but i have a feeling that was an approximation), then later when the location of the signals point of origin was found it was a region of space with no stars or really any thing at all.

The hosts speculated also if it was intelligent due it being in that really empty place in space and then we never saw it there again, it's likely the sender were simply in transit some where and we picked up some distant comunicqae of a "passing ship i nthe night".

although its like 900% more likley to be random noise or a misinterpreted signal from earth/[%]
Thats so wonderful and creepy at the same time.
It gets my dick rock hard
8 posts omitted. Click View Thread to read.
Alan Guth - Tue, 07 May 2019 00:53:29 EST VXVyTSl5 No.57680 Reply
might be drugs but I am pretty dang sure in the existence of alien life after seeing three circular pods bending spacetime. Lol drugs

high redshift mirrors

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- Wed, 06 Mar 2019 13:31:08 EST wIGiff+l No.57553
File: 1551897068878.jpg -(342947B / 334.91KB, 1000x1000) Thumbnail displayed, click image for full size. high redshift mirrors
lets say you were able to place a mirror in space out at such a distance that the mirror experience cosmological redshift from your perspective. If you were to shoot a laser beam of some wavelength at the mirror then the light reflecting off the mirror would be a longer wavelength than the originating laser because of the relativistic doppler effect.
what wavelength would the light be when it got back to you after bouncing off the mirror? would it be the original wavelength or would it be redshifted?
if its not the original wavelength then how was energy conserved?
7 posts omitted. Click View Thread to read.
Friedrich von Struve - Tue, 19 Mar 2019 07:34:25 EST izGRJ+VN No.57577 Reply
I don't think there is any information lost from redshift. It's the underlying space that is expanded during redshit, not the lightwave itself.
If you are in a reference frame that negates that expansion, you get exactly the "original" wavelength.

So I think this "relativistic reference frame" telescope would theoretically work.
There are some practical considerations though:
Pointing a telescope in the direction of travel means it is exposed to all the interstellar dust.
So you maybe need a vanguard of other ships that absorb it so it doesn't wreck you instruments.
Apart from that I think we could actually calculate if it's feasible to move that fast at all, drag of the interstellar medium becomes significant once you hit a considerable fraction of c.
Charles Bolton - Tue, 19 Mar 2019 19:11:02 EST 457vC2+I No.57578 Reply
In star trek sci fi shows they use electromagnetic fields to control interstellar dust. Could it be simple as ionizing the telescope? Also, though it would negate some of the benefits of having a large aperture to observe large wavelengths, if the telescope was quite small it might be possible for it to exist entirely within the bowshock of a forward facing shield. Would limit its field of view, but directly forward objects might not be the ideal candidates anyway because of the blueshift thing.
Paul Goldsmith - Wed, 20 Mar 2019 05:55:06 EST 4o5sH+7r No.57579 Reply
>Pointing a telescope in the direction of travel means it is exposed to all the interstellar dust.
destroy everything in your path using the power of relativistic beaming

Cartoons are not proof of reality. NASA is lying to you.

Locked View Thread Reply
- Thu, 07 Mar 2019 04:07:18 EST IqZLNWNv No.57557
File: 1551949638680.png -(433910B / 423.74KB, 752x768) Thumbnail displayed, click image for full size. Cartoons are not proof of reality. NASA is lying to you.
>Look at every post on this page.
ALL CGI and CARTOONS, no real images of Earth or anything from over 100 miles high. BIG RED FLAG.

>NASA and affiliated agencies have not been to space.
>Nobody has ever been over 100 miles high.
>Physics demonstrates to us that's as high as anything can go - which is why all images from over 100 miles up, are CARTOONS.
IT ain't rocket science ya know...

>The implication here, is that you were lied to as a child by government agencies and told you lived on a ball shaped Earth with no exit... A prison planet.
>You were born into a Jew run slave labor colony, and fed bullshit as you grew up.
It is not your fault.
>Jesus and God are not real. Evolution is bullshit, Globe Earth is a cartoon, and the Big Bang theory was created by a catholic priest.

If you are a science minded person, understand the ball shaped potato Earth is not real, it is bullshit, and does not exist in the real world outside of bogus math equations and cartoons.
8 posts and 8 images omitted. Click View Thread to read.
Annie Cannon - Thu, 07 Mar 2019 04:27:52 EST IqZLNWNv No.57568 Reply
1551950872680.jpg -(191330B / 186.85KB, 960x742) Thumbnail displayed, click image for full size.
>Quoting “Heaven and Earth” by Gabrielle Henriet.
“If flying had been invented at the time of Copernicus, there is no doubt that he would have soon realized that his contention regarding the rotation of the earth was wrong, on account of the relation existing between the speed of an aircraft and that of the earth’s rotation.

If the earth rotates, as it is said, at 1,000 miles an hour, and a plane flies in the same direction at only 500 miles, it is obvious that its place of destination will be farther removed every minute.

On the other hand, if flying took place in the direction opposite to that of the rotation, a distance of 1,500 miles would be covered in one hour, instead of 500, since the speed of the rotation is to be added to that of the plane.

It could also be pointed out that such a flying speed of 1,000 miles an hour, which is supposed to be that of the earth’s rotation, has recently been achieved, so that an aircraft flying at this rate in the same direction as that of the rotation could not cover any ground at all.

It would remain suspended in mid-air over the spot from which it took off, since both speeds are equal.”


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- Thu, 21 Feb 2019 04:17:57 EST 5UfVWq6v No.57539
File: 1550740677849.jpg -(7043B / 6.88KB, 300x168) Thumbnail displayed, click image for full size. Gravitons
While we were all out I was wondering about gravitons. If they're analogues of photons in a sense then gravitons should exist in a spectrum like photons, etc. Our ability to manipulate and understand the photon is pretty miraculous, but how would something like a prism for gravitons work? Prisms function with light because the speed of light in the medium is different than it is outside, what is there that could change the speed of a graviton or reflect it?
4 posts and 2 images omitted. Click View Thread to read.
George Gamow - Fri, 01 Mar 2019 15:11:37 EST 457vC2+I No.57547 Reply
You're pointing out the intellectual poverty on a meta-theoretic level of standard cosmology, and I think for some people that's so obvious as to not need statement, but most rank-and-file academics and science-literate people are still wholly convinced that LCDM has everything figured out, which is why we're stuck where we are. I think the reason you're seeing such a marked uptick in hangwringing over LCDM in the literature is precisely because the 'average' physicist has been exposed to these realities long enough to realize just how little ground they cover, and for just how long science is willing to wander into blind alleys, and are now figuring out how to communicate that to the faithful masses. Actually making a fundamental revolution in theory on the order you're suggesting (something that could recontextualize relativity) would create a shockwave in world affairs just as severe as Einstein's discovery did. So I would suggest it's not just that science has become dogmatic, or that scientists and people in general are buried under waves of distraction (which were all, incidentally, made possible by the scientific breakthroughs of the previous generation) but that the broader socio-cultural conditions aren't favorable to another drastic change. There are plenty of people who have alternative concepts, but it isn't in the zeitgeist to take them seriously, especially during the process of the breakdown of the current zeitgeist whose intellectual foundations lie in the previous wave of discovery.

So what I'm really saying is, wait 20 years. Breakthrough does not come out of comfort and distraction, it comes out of strife on the edge of oblivion. Einstein came up with relativity in a filthy trench under artillery bombardment -- and don't think that European academia's willingness to jettison the luminiferous aether in the face of relativity had nothing to do with national spirits broken by adherence to the previous centuries' failed philosophies and perspectives.

Democritus came up with the atom and Alexander of Hero came up with the steam engine thousands of years before either would become accepted and used, and not because of any particular flaw in their inventions, but because the broader social conditions were not favorable to an intellectual/cultural revolution at that time. So it is now for any bright physicist trying to find the holes in the standard model; only just now is the bulk of the science responding to the reality that a few luminaries could probably have told you in 1950: we're heading into a dead end. In 20 years a new generation will have come up with the failure of LCDM as their base view, and the time might be right for a change.

One last thing--
>>maybe the mass is emitting space.
Would this be observationally different than a curved space? Not saying you're wrong, but maybe you're just expressing a different way of verbalizing the exact same concept. If there is 'more' space in the same volume of space (the distance between point A and an egg and point A and a neutron star the size of the egg are the same, so a sphere with their centers at its circumference would have the same volume regardless of either's mass) then how could 'space' fit more 'space' in itself other than by curling it up/curving it? In fact I think that's a pretty succinct way of describing what's going on with gravity.
Thomas Henderson - Sat, 02 Mar 2019 02:52:25 EST aGo2dCNY No.57549 Reply
All of what your wrote about societal unwillingness to accept new discoveries rings true even if does seem so stupid. Greeks could've had steamships, but they were already satisfied with what they had? Oh well, too bad for them I guess.
The Wright brother's invention wasn't acknowledged by the general public until years after they'd been flying.

The idea of space or time being created beyond the event horizon must be a retarded alternative explanation for the apparent expansion of the universe given that it takes place beyond the event horizon, I just pulled that one of out my ass when I was wondering what happens at the bottom of a gravity well when it changes from being part of the curvature to the XYZ plane into being a hole with sides that are nearly or eventually perpendicular to the XYZ plane.

Sagittarius Dwarf Galaxy: Home?

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- Fri, 19 Oct 2018 18:25:45 EST 457vC2+I No.57470
File: 1539987945247.jpg -(20518B / 20.04KB, 485x313) Thumbnail displayed, click image for full size. Sagittarius Dwarf Galaxy: Home?
>>original article

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.

-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

-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 U4u72hWB No.57541 Reply
1551005559017.jpg -(562908B / 549.71KB, 1593x1080) Thumbnail displayed, click image for full size.
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 457vC2+I No.57542 Reply
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 rNBxnMOH No.57573 Reply
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?

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!!vVWR8L52 - Mon, 29 Oct 2018 19:21:02 EST F2wgR3l2 No.57479
File: 1540855262478.jpg -(184582B / 180.26KB, 1200x674) Thumbnail displayed, click image for full size. No flat earth thread?
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


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 Q1CtxL06 No.57530 Reply
apostrophes are an Illuminati conspiracy, get woke fool
Georges-Henri Lemaitre - Fri, 07 Dec 2018 16:17:18 EST fA4CdeQA No.57532 Reply

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 wlUjYsjb No.57538 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?

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- Thu, 18 Oct 2018 20:49:56 EST gVSzJCUs No.57466
File: 1539910196953.jpg -(74041B / 72.31KB, 600x399) Thumbnail displayed, click image for full size. How did such an inconceivably awesome object get stuck with such a stupid name?
"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 gRsMKZUR No.57520 Reply
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
Riccardo Giacconi - Wed, 05 Dec 2018 10:01:26 EST IpCFcmN3 No.57526 Reply
1544022086421.jpg -(409398B / 399.80KB, 1920x1080) Thumbnail displayed, click image for full size.
that kind of a technical answer i needed, thanks. sorry for being a clueless plebian.

Mars eclipse

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- Sun, 25 Nov 2018 21:39:22 EST ckw062Hz No.57504
File: 1543199962719.jpg -(58789B / 57.41KB, 978x459) Thumbnail displayed, click image for full size. Mars eclipse
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 457vC2+I No.57505 Reply
Naw, not with the naked eye. Phobos, the larger moon, is only 27 km across.


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- Thu, 01 Nov 2018 23:18:58 EST 7ez/W0kB No.57485
File: 1541128738303.jpg -(4349B / 4.25KB, 300x168) Thumbnail displayed, click image for full size. /STEM/
Slow board, maybe we should have /stem/
Subramanyan Chandrasekhar - Fri, 02 Nov 2018 03:15:02 EST m8u2eXUq No.57486 Reply
1541142902535.jpg -(56782B / 55.45KB, 720x638) Thumbnail displayed, click image for full size.
Everyone is planning a space party lately

Maybe they need more time to planet.


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- Thu, 01 Nov 2018 22:59:06 EST 6fcUdTGI No.57484
File: 1541127546853.jpg -(256320B / 250.31KB, 1280x1281) Thumbnail displayed, click image for full size. duuuuuude
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

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- Sun, 30 Sep 2018 09:15:14 EST 9RKOIT3O No.57458
File: 1538313314587.jpg -(134701B / 131.54KB, 835x557) Thumbnail displayed, click image for full size. Dark Matter and GR - struggling to understand
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 457vC2+I No.57461 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?
>>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 8/fKg+Ea No.57462 Reply

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

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- Sat, 16 Dec 2017 22:22:45 EST hGyQlc1t No.57130
File: 1513480965587.gif -(117244B / 114.50KB, 323x402) Thumbnail displayed, click image for full size. That FTL means time travel meme
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.
Bart Bok - Sun, 30 Sep 2018 09:42:04 EST 9RKOIT3O No.57459 Reply
>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 9RKOIT3O No.57460 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

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- Fri, 28 Sep 2018 00:48:46 EST 9ugkcJUP No.57457
File: 1538110126824.jpg -(74637B / 72.89KB, 548x550) Thumbnail displayed, click image for full size. Interchan Warning System


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Bernhard Schmidt - Thu, 15 Nov 2018 20:29:27 EST rNBxnMOH No.57496 Reply
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All weebs should be shot nb

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