Star Walls

7 hours ago, John Cuthber said:

OK, I had a look
 

  Reveal hidden contents

 

The numbers of dots are 

 1,2,3
2,3,4
3,4,?

That strongly suggests that there are 5 dots in the last box. That rules out answers 5 or 6

Each box has 4 quadrants- we can call them N,S,E,W
Solid dots are only allowed in the North and South quarters, but not in the East or West ones
That rules out answer 2

Unfilled circles are only allowed in the east or west quarters, but not the North or South ones.
That rules out answer 3

So we now have two options, 1 and 4


In any column, no quadrant is occupied more than once.
That rules out 4
(and you can do the same with rows)
So the only answer left is 1

 

 

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7 hours ago, michel123456 said:

  Reveal hidden contents

In each square, Up &  down dots are black, left & right are white. Existing serie 1,2,3,4, so 5 is the expected answer. The only solution that fits both conditions is solution 1.

 

 

A well reasoned post, Ghideon. But

Anyone know the answer to this? It might just be made-up to bait people but I was thinking

On 4/12/2020 at 5:18 PM, Sensei said:

 ...embarrassing scene in Star Wars universe:

 

Attack of the Groans.

Anyway, galaxies were originally mistaken for stars, I believe. And some or all of the images we're talking about must have been captured using out of date equipment, given their age, so not the best quality. Could gravitational lensing then explain this, duplication of galaxies mistaken for stars or perhaps simply copies of stars in the Milky Way? Fingers crossed this is not the work of ETs seeking to harness the energy of all the stars in the MW as the Sun could be next! The idea that they might be doing it to cover up evidence of their existence seems rather odd to me; what could be more conspicuous than a star that suddenly and inexplicably vanishes?

4 hours ago, Strange said:

At the earliest time that current physical theories can be applied, it was a quark-gluon plasma, I believe.

So the simulation begins some time after the big bang? That makes sense and thank you and Sensei for the replies. However, what I was more interested in was how they delt with the problem of the asymmetry between matter and antimatter. My appoliges if you already explained and I'm being obtuse.

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Then someone invented the Internet and here we are

Agreed. Thank you, Al Gore!

An impressive enough feat I won't claim to fully understand. Still, I have some questions: firstly, I was under the impression that dark matter was something that could only be *inferred* from the rotation of galaxies etc. [Not really a question, but I'm still warming up.]

And I thought that the universe at its very beginning consisted only of pure energy, photons. How do they go from pure energy to TNG50 galaxies?

Also, how accurate is simulation which contains only 20 billion particles likely to be when galaxies contain 100s of billions of stars and trillions of atoms?

It doesn't help that when I searched for "TNG 50" I got this:

29 minutes ago, Eise said:

As far as I remember, a type 1 'multiverse' is not really a multiverse: it is an infinite universe. An infinite, spherical universe does not make sense to me (but if some cosmologist knows that this would be meaningful I hope (s)he will chime in),  but then we are still left with a flat universe, a parabolic or a hyperbolic universe. But you are right, nothing (at the moment!) points to a parabolic or a hyperbolic universe. And 'repeating' might be a to strong expression. One should always be very careful with 'infinity'. You cannot think about infinity as just a big number. 

Okay. I read a thread a while back that you posted in and was impressed by the arguments you made even though opinion in the thread seemed to be mainly against you, and even though much of what was being said was above my head. I think it was on the subject of time and the line: "loop endless: see endless loop" came up. Anyway, my suggestion was that a closed "loop" universe, where you arrived back where you started, might be indistinguishable from one on a flat plane, where you just kept going until things repeated. What do you think?

19 minutes ago, Eise said:

I wonder if you know yourself what you are asking. What has a flat plane to do with 'the idea of the multiverse' (which idea exactly? Many worlds theory? Bubbles in the inflational universe? Infinite universe with repeating patterns?). How can two points be indistinguishable and not be the same? If they are not the same, they are distinguishable per definition. (And how do points differ anyway?).

There are two types of universe being purposed here, are there not ? One, on a flat plane, Euclidean. And one on a spherical plane. Has it not been suggested that on the first type, at least, there exists such a thing as a type 1 multiverse, where everything would repeat after a certain while?

1 hour ago, Strange said:

So far. That is not because we are measuring from "inside" but simply because the possible deviation from flat is very small.

Not really. It is moralise saying whether space is Euclidean (for example, the angles of a triangle add up to 180º) or curved (like the surface of a sphere where the angles of a triangle add to more than 180º). In the latter case, if you travelled far enough, you would end up back where you started (ignoring the fact that the universe is expanding).

What if on a flat plane you traveled so far that, by the idea of the multiverse, you returned not to point A, where you started, but instead reached a point B that was indistinguishable from point A?

10 minutes ago, Strange said:

As the measurements in question were made within the universe, then the answer to would appear to be yes

But those results are inconclusive, are they not? But, I thought I was quoting Max Tegan more or less. And I forgot to ask if all these curves in fact correspond to a cannon ball either going into orbit, flying into space or hitting the ground?

Is it even possible to know the shape of the universe without stepping outside it?

Did John Wheeler not propose that there may only be one electron in the whole universe and that the positron is an electron moving back through time? If so, there might be no larger mass black hole, as the electron would in a sense be annihilating itself.

On 11/3/2019 at 12:57 PM, MigL said:

There is no lower limit on the size of Black Holes, just on available mechanisms for their formation;  gravitational collapse of stellar sized objects that lose antagonistic radiation and degenerate pressure, or additional mass acquired by a neutron star from a companion or interstellar gas/dust.
Both methods result in sizeable Black Holes.

However primordial Black Holes, formed in the hot, dense soup shortly after the Big Bang, could form in any size, and could have evolved in two ways.
They could have 'evaporated', due to their high temperature and resulting Hawking Radiation. These small BHs could have or be currently reaching the end of their 'evaporation', where they discard their event horizon and explode in a large gamma ray burst; we don't see any observational evidence of this happening anywhere.
Or they could have become the 'active' seeds of the supermassive BHs ( and their surrounding gas/stars ) we see in most all galaxies. These active BHs are numerous in the distant past ( great distances ) in newly forming galaxies, and are usually termed Quasars.

And/or could they perhaps be all around us? I've heard it proposed that the electron itself may be a black hole; and vice versa. Now, I've also heard neutron stars described as "atomic nuclei". If so, an event such as a black hole orbiting a neutron star might be interpreted as some kind of macro atom, which, like all atoms, might even emit radiation. Is it not true though that Einstein, himself, went to his grave convinced that black holes did not exist? He believed that something would always happen to prevent, or limit, one from forming.

9 hours ago, swansont said:

A solar cell that only absorbs green light? Is that really going to improve things? The solar cell gets less efficient, and the plant gets the same sunlight as before, just without the green. Things cool off a bit for the plant, which improves growing, perhaps. But you cut out maybe half the light for the cell, since the solar spectrum peak is in the yellow/green part of the spectrum. I'm not seeing that as a win-win, since you compromise the solar production.

There are applications where the solar cells are transparent, and only grab a fraction of the light, such as being used on top of windows in office buildings. (in development; I don't know if they are commercially available). Maybe you could apply the idea to greenhouses, where the emphasis is on plant growth rather than electrical generation (so the electricity would be the bonus), but for solar utility installations I don't see how it improves things

I was just thinking it's a waste of time chucking green light at plants. It gets reflected into space or wherever.  So, yes, something like a greenhouse that skims off the part of the spectrum the plant does not need. Meanwhile, our plant can happy produce oxygen and food. And, as you point out, the temperature drop could aid plant growth. And, yes, the emphasis would be on plant/crop growth and perhaps making more efficient use of land.

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You think there's a lot to be had in the efficiency of photosynthesis?

I believe in principle you can get up to 26% efficiency with photosynthesis; not easy in practice.  But It would certainly be progress if we could ever match, say, the efficiency of panels. You could have oxygen giving plants in place of those costly things.

Too bad we can't just create something like a Triffid and put it on a treadmill. But as some plants and vines are capable of movement, or at least of exerting mechanical force, perhaps the idea is not as crazy as it sounds.

As far as panels go, well, plants don't seem to like green light too much and end up chucking most of it back at us. Otherwise, we would see them as black. Am I right? So how about panels designed and positioned to take advantage of that?

Also, as I understand it, the efficiency of most panels, on the market today, is only about 20%. Meanwhile, the efficiency of plants, like sugar canes, is about 8% (chemical) and with advances in technology, those ratios could well change. Something to think about.

Hello. I hope this is the right place for such questions. I logged on to correct a typo. But I am unable to edit the post in question. I don't know if this is because of my status as a newbie or if there is a limited window to do it. It might even be a browser issue for all I know. I don't even really care if nothing can be done about it (no use crying over spelled milk). I'm really just curious and this seemed like a chance to notch up another post.

Edit: It would seem there is a limited window to edit your posts. Mystery solved.

^ Being *porked in exchange for a longer life? A pity the procedure could not have used a less tasty part of the animal. And I wonder if this operation preformed in reverse would result in a more or a less greedy pig. Wait. Aren't pigs, like, huge?

*so to speak

Interesting idea. Maybe it will get those Driller-fillers demoralized.

On 8/8/2018 at 9:37 AM, Sensei said:

A desperate thief can even drill a fuel tank..

I always felt that was one of the themes of Mad Max (n).

On 8/1/2018 at 7:40 PM, prashantakerkar said:

 

Is it possible to reverse play a Video file?
 

Sure. All you will need is:

Your existing media player.

Your existing television set or display device.

A pair of very keen eyes.

A space vehicle capable of traveling faster than the speed of light.

Method:

Set the file playing on your screen and wait for the program to end. Now don't hang about; get into your craft. I would advise plotting a course directly away from your TV. Now by traveling faster than c, you will eventually pass the photons that left your display. Which means by looking out the rear porthole you'll be able to see the movie running backwards. Of course, the further away from Earth you go, the smaller the picture will become. That is where the pair of very keen eyes comes in.

On 7/25/2018 at 10:09 PM, Sensei said:

Aren't you talking about "Dyson sphere".. ?

https://en.wikipedia.org/wiki/Dyson_sphere

That would be the way to go in the end. But as a first step how about an inverted sphere? Enclosing our world inside an increasingly dense array of solar panels.

If such a structure allowed us to choose how much light was received, that's global warming taken care of. And if the panels could be produced at our moon base of the future, that would probably be a lot less hassle than launching them into position.

On 7/26/2018 at 12:50 AM, Ken Fabian said:

I have always wondered if those transmission technologies for beaming down to Earth could be used to beam power up in one region on Earth to beam down in another, ie as a global power transmission system.

You mean put lasers in space that we can charge from earth? Also might a global power transmission system not lead to a global power company? All this has got me wondering if tin foil hats turned inside out can be used as solar panels.