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Showing content with the highest reputation since 10/26/20 in all areas

1. 5 points

FTL thought experiment

When you arrive at point C, you will see the same light coming from both stars as someone who never moved from point C; Light that left both stars 5 yrs ago. You see both stars as they were 5 yrs ago.
2. 5 points

The Official JOKES SECTION :)

Three of those images imply too much power in the wrong place. The other is a horse.
3. 4 points

How Trump Could Steal The Election

Hillary called Trump to concede on the same night as their election and their race was FAR closer than this one with Biden. Barrack Obama invited Trump to the WH a day or 2 later and made his entire team available to the incoming Trump admin to maximize their chances of quick success. Essentially every democratic leader and person with a national profile acknowledged Trumps win and congratulated him on his victory both privately and publicly. Nothing anywhere even remotely close to this has ever once happened before since George Washington as our very first president ever transitioned power to John Addams. Let’s not pretend for even one second that this is somehow a both sides issue.
4. 4 points

Political Humor

Recognize anyone ?
5. 4 points

Lol...
6. 4 points

Political Humor

Salute to 2020 Ice Cream Flavour:
7. 4 points

The Official JOKES SECTION :)

Translated by me from https://www.socomic.gr/en/2018/01/kourafelkithra-socrates/
8. 3 points

9. 3 points

Copenhagen Interpretation?

I agree with you, basically, that the Copenhagen interpretation is not satisfactory, and neither it is the many-worlds interpretation. But the Copenhagen interpretation works like a dream. That's the problem, actually. It works like a dream and mathematically, it cannot be the whole story. As Bell said, Copenhagen's interpretation is good FAPP (for all practical purposes.) As Bell also said, Mind you: He didn't mean classical-mechanical arguments; he meant quantum-mechanical arguments. I'm working on a miniature of explanation in 2-dimensional quantum mechanics, if you're interested. The many-worlds interpretation is not a corollary of the Copenhagen version. It's more like what @Sriman Dutta says: I totally agree with this. Conjugate variables are certainly peculiar. Their properties cannot be simulated by any finite-dimensional space of states and thereby cannot be completely understood with discrete mathematics. They are the domain of transcencental mathematics. Unlike the famous $$J_x$$, $$J_y$$, $$J_z$$ that people use in all the completeness theorems, they always pair in couples, one of which is conserved, the other is not.
10. 3 points

Brain in a vat hypothesis

We don’t fully know since it’s not currently possible to keep a brain functioning and healthy once it’s fully severed from the body that grew it. Whether you put it in a vat or an entry bag of Cheetos, this is all hypothetical. Keep in mind, however, (no pun intended) that the brain doesn’t really care about the actual interaction of atoms (as you call it) that occurs when a touch happens between the body and something out in the world. All the brain cares about is what nervous signals are arriving to its various parts, how intense those signals are, the duration of the signals, and in what order those signals arrive. This information is then all combined to form a “narrative” describing the event in our conscious mind... the part we generally consider to be the self... the “me” behind the eyes. So something presses against our skin. This change in pressure causes certain receptors to activate, and those receptors trigger a cascade to the receptors around them (nerve cell 1 activates nerve cell 2, and nerve cell 2 then activates nerve cell 3, cell 3 activates cell4, and on and on all the way up the spine until the signal finally arrives to our brain...then some new signals cascade throughout the brain much like ripples travel across a pond after tossing in a stone). But that is all... the only thing the brain “sees” is that a specific change in voltage happened at a specific nerve cell or set of cells. It’s only later once those incoming signals have been put together that the brain concludes that this thing which just happened was a touch... it then compares it against previous touch experiences to determine specifically what touched us etc. Following this same logic, you could theoretically send a signal to your brain in a vat separately. So long as that signal being sent to your severed brain mimics the signals sent to the brain from the body, then we can likely assume it would be perceived as a touch no differently than touches get perceived today. You’d clearly need to tune the signals like musical instruments in a symphony to achieve the right “sound” and there are lots of assumptions embedded here (like the fact that we’re successfully keeping a functioning brain in a vat somehow), but that’s my take. Hopefully it gives you some food for thought.
11. 3 points

Why is there no forum for (insert field here)?

Many historical 'facts' are contested and debated by historians. Things like the cause of the fall of the Mycenaean civilization, which, along with Crete, comprised the 1st Greek empire, fought a war with Troy, and literally disappeared from the face of the Earth. Things like did the Roman Empire really fall, or did it just 'absorb' invaders and convert them to the Roman way of life and governance. Things like the cause and mistakes in execution of the 1st World War. And its contribution to the beginning of the 2nd World War. Things like Papal authority ( even over Emperors ) and the amassing of power and corruption by the Church, along with wars encouraged by the Church and the selling of 'Salvation' which led to splintering into differing 'sects'. Things like was the Vietnam War winnable, and more importantly, was winning necessary or of benefit. Things like the paradigm shift that brought about the Renaissance. How many did you want me to list ...
12. 3 points

Is God visible!?

You assume too much. Shi'a and Sunni Muslims disagree about 'the roots': Who are the rightful heirs of Mohammed, and whether Al Bukhari was right about him and his doings, and probably many more things. I'm sure you know much more about it than most of us here do. It's a 'sources' problem (both about the authenticity of books and/or translations, and about the line of authority) very much like what was for Christians several hundred years ago in Europe between the many Protestant offshoots, and Catholics, and Jews. That led to unimaginable bloodshed between Christians and Jews. We know. Actually, we know much better than you guys do. We've killed each other, we've hated each other for so many more years. Most of us seem to have taken home the lesson. You, unfortunately, haven't. That's a very big part of the problem, guys. A part of your community seems unable to take home some lessons from your brethren religions that are much older than yours. Jewish and Christians being at each other's throats for centuries. You're still obsessed with a couple of lines in a several-centuries-old book. That's, allow me to say, pathetic. Both in the most ludicrous sense, and in the most tragic one. Take a look at Mandaeans, Yasidis, etc., and how they've become victims of unspeakable violence in recent years in the Middle East, just because they follow the rituals that their ancestors did. Probably with the same amount of doubt that you do yours. But also take a look at how some Muslims brothers die at the hands of each other because of a difference of opinion. And ask yourself: Is the interpretation of some lines on an ancient book worth the suffering that we see in the world? The suffering of a child is not worth ten thousand lines of a holy book.
13. 3 points

Is God visible!?

I, for one, wish posts like these about god were less visible
14. 3 points

Infinity has an end..

Infinity has an end? Infinity means many different things, depending on when it is used. The word is from a Latin word, which means "without end". Infinity goes on forever, so sometimes space, numbers, and other things are said to be 'infinite', because they never come to a stop. ... For example, adding 10 to a number repeatedly. Let me know when you reach the end...
15. 3 points

How Trump Could Steal The Election

...and after January 20... plus they have to get him out of there:
16. 3 points

Gravity and Space

No, the source of gravity is energy-momentum, which includes many more things other than just mass. For example, and electromagnetic field (in otherwise empty space) would also be a source of gravity, as would be stresses and strains in the interior of a planet (e.g.). It needs to be spacetime, not just space. It is not meaningful, in the context of gravity, to separate space from time, and vice versa. As to what spacetime is - it is quite simply the set of all events, meaning the set of all spatial locations at all instances in time. It is thus a mathematical model. No. When any test particle - irrespective of whether it has mass or not - is affected by gravity (and only gravity, for simplicity), then that means that its world line in spacetime is a geodesic of that spacetime. It is a purely a geometric phenomenon. When space is expanding, that means that the separation between any two points within that space increases over time. However, locally those points remain at rest - you can attribute a relative velocity to these specific points, but not to space (that would be meaningless). Relative motion is not a source of gravity, so it does not 'warp' spacetime. What GR does is model the motion of test particles in the presence of sources of energy-momentum; as such, its predictions are quite physical indeed. This is just what Newtonian gravity does, and such a model works quite well in the low-velocity, weak field domain. However, once you venture further into the strong field regime, the predictions of Newtonian gravity are no longer accurate. And even in the everyday low energy domain - consider putting an accelerometer into free fall (drop it off a tower etc). It will read exactly zero at all times while it is falling - and zero acceleration means no force is present. And yet, the falling accelerometer is very clearly still affected by gravity. So gravity cannot be a force in the Newtonian sense. There are also deeper, more technical reasons why gravity cannot accurately be modelled by a vector field. You cannot accelerate a massless test particle. You have every right to be, because the way GR is generally presented does indeed make it confusing, once you give it more than just a passing glance. Spacetime is not a mechanical medium, so curvature is not any kind of mechanical 'bending'. As mentioned above, spacetime is simply the set of all events, and the geometry of spacetime can be thought of as how these events are related to one another. If the geometry is flat, then that means the relationship between any pair of neighbouring events will be the same, regardless of where/when in spacetime you are (like on a flat sheet of paper). If spacetime is curved, then this is no longer true - the relationship between a given pair of neighbouring events depends on where that pair of events is located in space and time. That's the meaning of curvature - a change in the relationship between events. It's a geometric property, not a mechanical action. This is analogous to the longitudinal lines on a globe - at the equator, they are spaced apart by a specific distance, but as you go north (or south), that distance will change, even though these lines are perfectly straight within the surface. That's because the relationship between points on those lines changes depending on where you are, since the surface has intrinsic curvature. Spacetime is the same, just in two more dimensions.
17. 3 points

Comparing Corona Virus Success Stories with Abysmal Failures

It has nothing to do with 'spinning' the death toll, JC. His policies, such as pressuring State Governors to re-open, and lack of policies, such as not making medical supplies available to certain States, have led to the situation in the US. Canadians and Americans are generally very similar, and our own response has been far from perfect. Yet Canada, with 1/10 of the American population, has 42x less infections. And 23x less deaths
18. 3 points

19. 3 points

Faraday's law of induction is not true

I recall when I was a teaching assistant there was a lab on Faraday's law. You had a coil with some number of turns, and you flipped it and looked at the induced current in a circuit. Students used it to deduce the earth's magnetic field. And it worked reasonably well. One fun part of this was that students on one corner of the room got a different answer because there was an NMR lab one floor up, and when that magnet was on, it was strong enough to affect the field in that corner of the room. So they got a number noticeably larger than students at the other side of the room.
20. 3 points

Examples of Awesome, Unexpected Beauty in Nature

Volcanic lightning is hard to beat. https://en.m.wikipedia.org/wiki/Volcanic_lightning Calbuco, The Awakening.” ... Calbuco Volcano is located in the lakes region south of Santiago, Chile’s capital city and is one of the 10 most dangerous volcanoes in the country. After more than 40 years of inactivity, the day April 23 the volcano erupts, spewing more than 200 million tons of ash https://www.dailytelegraph.com.au/news/photos/national-geographic-photo-contest-2015/image-gallery/a2afa2087ecd4f4d62475d231b129e31
21. 2 points

22. 2 points

Examples of Awesome, Unexpected Beauty in Nature

Icelandic ice cave (I use this image as background of my lock screen) , Dripstone cave in Germany
23. 2 points

RIP Sean Connery

Very sad news, a legend of film, and the pride of Scotland, has passed. The orginal ( and best ) James Bond, Captain Remus. Jimmy Malone and John Mason, has passed after a distinguished career. Remembering Swansont's previous avatar, I offer my condolences.
24. 2 points

The Official JOKES SECTION :)

If you could kick the person in the pants responsible for most of your trouble, you wouldn’t sit for  a month (Theodore Roosevelt)
25. 2 points

What is the Big Bounce and what evidence and arguments are used to support it? Or counter it.

Biggest problem with all versions of cyclic cosmologies is the fact that entropy has to be 'reset' to the low initial state. One mechanism proposed by R Penrose with Conformal Cyclic Cosmology is that all particles have to eventually decay. And while a proton decay is possible ( even with other theories ) after more than 1032 years, the decay of fundamental fermions is a lot tougher to come to grips with. https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology
26. 2 points

Gallium/Mercury Planet

Just doing quick mental calculations ... Mercury solidifies at a pressure of 14 Kilobar, which is approx. 14000 standard atms. That is equivalent to approx. 420 000 in of Mercury, which is 35 000 ft, or approx. 6.5 miles. IOW your hypothetical planet would have a Mercury 'sea', 6.5 miles deep, surrounding a solid orb of Mercury. Not sure about Gallium, as it expands when 'frozen' ( like water ).
27. 2 points

28. 2 points

ChatBot using Markov Chain: how to understand the intent of user?

What's the purpose of the project? Are you focused more on learning how programming a chatbot works, or do you just want a working product (or something else)? The full model has 175 billion parameters. Crazy stuff. I heard rumour that GPT 4 will have 20 trillion parameters. How much do you think just making bigger models and feeding them more data will improve outcomes?
29. 2 points

In between 3000 BC 1400 AD

But since the OP specifically used "BC" and "AD", which are not used in the Hindu calendar, that is not relevant here.
30. 2 points

Wow it looks like God really does exist

Maybe it's just the timing, but I don't remember being this disgusted by a religious assertion before. It shows a myopic and desperate need for privilege that ignores reality. This is the stance that can justify wiping out species wholesale, because they were only put there "for us to enjoy". It's also intellectually dishonest to misuse scientific claims to bolster your shaky belief system. Please stick to your Iron Age sky spirit worship.
31. 2 points

Subjective flow of time

That's a great answer. I remember when I was a kid my summer holidays felt like an alternative life. Full of experiences that seemed like brought from another world.
32. 2 points

33. 2 points

Does Classical Gravity exist in the "atom."

So many misconceptions. So many wrong assertions. Remember what I said about looking stuff up, before putting your ignorance on display ? Ask one question at a time, and don't go jumping to conclusions. The only gravity there is, is classical, whether Newtonian or GR. Yes, atomic particles interact gravitationally. For an atomic particle, the Electromagnetic interaction is approx. a billion, billion, billion, billion times stronger than the Gravitational interaction. The Strong interaction, mediated by gluons and binding quarks below its asymptotic limit, is 137 times stronger than the Electromagnetic interaction, but only 'residual' force binds nucleons inside the nucleus, and quickly drops off after that. So why would you conflate the two, and go on to make all the other ignorant assertions ???
34. 2 points

How Trump Could Steal The Election

If not considered in earlier discussion, this election was a referendum on Trump that likely owes victory to Republicans rather than Progressives, Democrats, or some other independent affiliation. The evidence for this is suggested by the loss that House Democrats experienced and their failure to make significant gains in the Senate despite Biden's nearly 5 million more popular votes than Trump. This significant margin of popular votes suggests to me that a large number of Republicans crossed party lines to vote for Biden while continuing their support for down ticket Republicans. If other affiliations were responsible for Biden's victory, they likely would have also elected a congress that would likely support rather than potentially obstruction his administration's goals.
35. 2 points

Has it ever occurred to you that the inherent paradoxes involved in time travel, such as any causality breaking or 'grandfather' paradox, suggest time travel is unreal ???
36. 2 points

Layered Mesh Optical Illusion

When a grid's misaligned with another behind, that's a Moiré https://xkcd.com/1814/
37. 2 points

Does everyone pretty much have the same built-in framework for thinking?

It may seem linear, but when you think you're drawing from relevant sources you've been accumulating since birth. You choose the knowledge you need to apply to a situation from a large range of information you've previously put together from selected data. It's like your box of tools to deal with a particular problem. If you need to fix yourself something to eat, you're going to think of just those things you need to make it happen, and select the ones that will successfully turn your thoughts into action. As you gain more experience, your knowledge is broader and deeper, so the information you're able to draw from is richer as well. It's pretty amazing, really. The moment you feel hungry, your mind starts grabbing all the knowledge available to you, including your current preferences and available resources. You fill your tool box with what you need (no money but stuff in the fridge to make an omelet, grab a pan and a bowl and a spoon, turn on the stove, get the bacon, etc), and don't bother with anything else (you didn't grab the cat brush, or start your car, or check to see if you have any blue paint). Change the parameters of the situation, and your thinking is going to change as well (hungry roommates need food too, or the eggs went bad, or you find a bunch of money). It's a lot more than going from a to b to c to d.
38. 2 points

39. 2 points

FTL thought experiment

Neither. You moved (impossibly) on the "grid", but as described you simply did it all in the same frame . Points A, C, and B are all in the same frame and you moved spatially only in that frame. You would have travelled forward or backward in time in some other frames, but not in that one. So you travelled in time relative to neither star.
40. 2 points

First Post on Primes

Now that I think about it, the product of the first 23 is, as you say, 223092870. Now, the number of ways in which you can sum two (arbitrary) natural numbers to give N is just 111'546'435, because 223'092'870 is even. So the problem reduces to finding how many numbers there are between 1 and 111'546'435 that are not divided by 1, 2, 3, 5, ..., 23 (the 1st 23 primes). The only thing I can say is that's not an elementary problem. How did you get your conjecture @Tinacity? Counterexample: $$\pi$$ is irrational; $$1-\pi$$ is irrational too. but $$\pi + 1- \pi = 1$$.
41. 2 points

Supersonic sub (split from Speed limit on earth)

There are two types of fluid flows in aero/hydrodynamics, compressible and incompressible. They can both be modelled by little springs between each fluid particle; when you push against one particle, it pushes against the next via the little interconnecting springs, and the fluid, in effect, compresses. If you push too fast, the little springs reach maximum compression, and the particles begin to 'pile up' into a bow wave. For air, this happens at Mach 1, and the air effectively becomes incompressible. Water is nearly incompressible from the get-go ( also, liquids and solids have transverse 'sound' waves as well as longitudinal ). That's why you see a bow wave on a boat doing 10 mph. That wave is the 'shock' of the particles bunching up because they can't move out of the way fast enough. Another ( huge ) problem would be cavitation. This is usually seen in pumps/propellers where the fluid can't flow fast enough into the area behind the pump/propeller blades, creating a low pressure area ( or even vacuum ) which tends to destroy equipment. For a plane the shock is the separation where supersonic air is drastically decelerated to subsonic ( inside the shock cone ), and it carries a lot of momentum/energy which is dissipated in the 'sonic boom'. If the 'sub' was at a shallow depth, with the surface close by, the spray pattern of the water shock into the air would be extremely interesting. to say the least. So the shock wave of travelling through water would be no different than through an incompressible fluid such as supersonic air, except for the cavitation problem, which I didn't consider on Sunday ( and which may make this idea a non-starter ).
42. 2 points

Extraterrestial life searching

Im not sure if this is the right place to ask, the right category, the righr dorum etc. Also im only 15yo so dont explain in too professionam terms please. But ive always wondered this... When people bring up searching for extraterrestial life its always about if water is present on the planet, why is this? I know we live from water and so do fish, where we originally originate from and the bacteria they originated from lived in water but i dont see this as proof. Cant evolution on a planet without water just work with chlorine for example, or an element not even present on earth and thus not known to humanity. Same applies to distance to the sun to have a temperature sweetspot, wouldnt another planet have life evolved to their temperature? I mean we have had animals for ice ages and, well, not ice ages... unless you really are able to prove me wrong here i feel lile we need another planet with this theory proven for it to be sure. Im not trying to start the next flat earth like community but im just trying to understand.
43. 2 points

what does "scientist" mean,exactly?

A scientist is someone who does science. You can make a distinction between professional and amateur, but those are modifiers/distinctions within the category — both are scientists. A scientist who becomes unemployed doesn't suddenly forget how to science. You can also make a distinction about the level of training. But someone without a degree who is doing science is a scientist. These days it's unusual, but go back a while, and training wasn't quite as formal. There have been largely self-taught scientists, and others who were informally taught, for at least part of their background. Einstein had defended his thesis, IIRC, when he was employed as a patent clerk and wrote his papers in 1905; he did this while looking for a professorship (much like actors and actresses wait tables between gigs if they haven't made the big time). He was a scientist.
44. 2 points

how much of the outer universe can we see from where we are?

That "Narrow band" is a lot wider than it looks to the naked eye. You are only seeing that part that is bright enough. As an example, consider the Andromeda galaxy. To the naked eye it looks like a small fuzzy spot, but if you could see it in full, it would appear like this in the sky. Several times wider than a full Moon. What we see by naked eye is just the nucleus of the galaxy. But just because we don't see the disk by naked eye doesn't mean that it doesn't hide the light from galaxies behind it.
45. 2 points

what does "scientist" mean,exactly?

I'm sure that would be a surprise to the Olympians who won gold medals back when competitors had to be amateurs.
46. 2 points

Can science prove the existence of an intelligent world that rules our universe? Split of Theory of everything

Mostly because; he/she/it has no idea what he/she/it is talking about.. Please do, however, I can't promise to shit in the right place...
47. 2 points

Faraday's law of induction is not true

[T]he fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown. — Carl Sagan Alas, to wear the mantle of Galileo it is not enough that you be persecuted by an unkind establishment, you must also be right. — Robert Park ! Moderator Note Showing that you are right requires experimental confirmation. It also requires that one be able to try and falsify your idea. And I have provided an experimental result that falsifies your idea (it is completely unsurprising that you dismissed this without justification and have not pursued it further. Instead, you repeat your assertions). Plus descriptions of other experiments that confirm Faraday's law. Others have pointed out that motors and generators run in accordance with Faraday's law, and would not work if things were as you claimed. So what I mean here is that quoting Schopenhauer and invoking the fallacious "if you are resisting I must be right" stance implies you have no evidence to present. You were given the opportunity, and you chose not to. There's no point in wasting more of anyone's time. Don't bring this topic up again.
48. 2 points

Can science prove the existence of an intelligent world that rules our universe? Split of Theory of everything

Why couldn't it be revealed?
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