Admittedly a bit of an oversimplification. It’s from a YT video: a chocolate bar costs £1 but four wrappers gets you a free bar. How many bars can you get for £1000?
So you buy 1000 bars which gets you 1000 wrappers. Turn those in for 250 bars. With those (actually 248) you get 62 bars. Add the 2 from before and turn in 64 wrappers for 16 bars. And again for 4, then 1. It’s a sequence of quarters and the solution is 1,333.
Recent as in the last couple years but when I was diagnosed with ADHD, I realized that most people dont have an interest driven brain. They can just do boring stuff just as easily as fun and engaging tasks.
That people with mental health issues hear different types of voices depending on the country. If someone with schizophrenia from the US hears voices, it is more aggressive or negative while someone from Africa or India might hear a more playful voice. I think that says a lot about the different cultures and upbringing.
Ah so not America but the Internet rather. If its the Internet, Im fine with it. I intentionally avoid news sites and ragebait. Think of it logically. It wont really do anything to your life really. No need to keep reading these.
That certain tribes who live in a jungle setting can discern and have names for about 40 different shades of green, where a city dweller would see them all as being exactly the same shade.
I think I’ve read before that our eyes are most sensitive to the color green out of any other color, something about it that wavelength of light is absorbed more readily by the cones in our eyes. Being exposed to it daily and maybe having their survival dependent on it probably helps them develop that ability.
Another one is how Eskimos have 53 words for “snow”, not just “powder” and “slush”, but everything in between and beyond.
Fun fact: if we could see through the intensity of sunlight to pick up its’ color, it turns out green light is the most prevalent photon wavelength.
Surely this and phenomena like photosynthesis are directly related.
Do you have a source? There is a common myth that innuits have 100+ words for snow, which is stretch beyond any reasonable sense, I’m afraid this might be similar.
The peoples I had heard of previously, are the Himba tribespeople, with a ‘hyper-perception’ of green hues.
This is an ongoing research area, and I was hoping someone in the field could outline the recent key changes in understanding of cultural effects on colour perception.
There are papers such as this one, that I can partially follow, but would benefit from an interpretation from others more knowledgeable than me.
I watched a video about the development of the line, that ridiculous building project in the dessert. I see glacier basically melting in front of my eyes but never felt as doomed as watching this shit developing for some reason. Just the sheer amount of manpower, diesel and money wated on the viggest pile of shit i have ever seen while the planet around them is dying.
If you’re on a truck traveling at 60mph, and throw a ball forward at 60mph, that ball is moving at 120mph.
But if you replace the ball with a flashlight, then the light isn’t moving at the speed of light plus 60mph. Instead, it slows down so as not to exceed the speed of light.
It’s like if you threw that ball at 60mph and it went flying forward, but at 10mph, no matter how hard you throw.
I had the Relativity conversation with my 16 year old this past weekend, as he is taking AP Physics.
Yeah, he couldn’t wrap his mind around it. Honestly, I can’t say I understand it very well. I get that C (speed of light) is C in all reference frames. What I do not understand is for a spaceship traveling at C, the forces being transmitted between the atoms from stern to bow are unable to catch up to the next forward atoms. Hence time dilation, at least for those forces being transmitted “forward” in the ship’s reference frame.
However, what happens to those forces being transmitted bow to stern or “backward” in the ship’s reference frame? Would those forces be “dead stopped” in an external reference frame? Yet travel at C from bow to stern in the ship’s reference frame? What does that mean for the ship if those forces are only being transmitted one way?
Or, as I very much suspect, do I just not have a clue as to how it really works. I always thought that “time dilation” was simply the inability of forces being transmitted from atom to atom. As those forces are limited to C and they are attempting to catch up to another atom also traveling at C. With that said, those forces are transmitted in multiple directions, not just the vector the ship is on.
Ok, another one of my very few brain cells just committed suicide and I’m not drinking anything, so I’ll stop now.
My understanding is that it’s impossible for a spaceship or anything else with mass to actually reach the speed of light. It can only approach it. Only massless energetic waves like light and radiation can travel at the speed of light.
Your understanding is correct.
Relativistic mass increases the faster the moving object gets. That in turn means more energy is required to accelerate an object the closer it gets to the speed of light.
Fun fact: the speed of light is not as absolute as it might seem when looking at relativistic effects. In media with a refraction index above 1 (only perfect vacuum has a refractiom index of 1), the speed of light equals 1/(refraction index).
For light moving in water that results in a speed of light of around 3/4 the speed of light in vacuum.
Uhh, relativity, fun. This gets a lot more mind boggling, imagine 3 people, A and B are in a train and C is an observer outside. From C point of view, B will pass him first, then A. This train is going at 50% the speed of light and it’s very long, A and B are 1 second light apart, i.e the distance that light takes 1 second to travel.
If A shines a flashlight B will see it 1 second later. However from C point of view since the light was shone the train moved forward 0.5 light seconds. So the light has to travel 1.5 light seconds distance, and it does so in exactly 1.5 seconds. So the observers disagree on the distance the light travel, but also disagree on the time it took, but they agree on the speed of light.
This makes things weird, because both A and B say that 1 second passed, but C says that 1.5 seconds passed. This means that people moving faster experience time slower. Which means that if you take two twins, put one on a fast moving ship, e.g. 80% speed of light, by the time he comes back only a few minutes would have passed for him, but years would pass for the other.
There was once an experiment where a particle traveling at 99.999…% the speed of light aged 1 second in 5 minutes. Conclusively, next to lightspeed moves time 300x faster than our speed in universe + gravitation dent.
Question: is even faster time possible in a huge enough gravitation dent (neutron star)?
At 99% speed of light you age 8.5 seconds per every minute. At 99.9% it’s 2.7 At 99.99% it’s 0.85 At 99.999% it’s 0.27
At 99.99944444% it approximates what you described, with 1 second becoming 5 minutes. But you can keep adding 9s, at 99.99999% one second becomes over half an hour, and at 99.99999999999999% it becomes over 2 years.
So on and so forth, so at 99.999…% like you said it’s essentially 0 seconds vs infinite time.
I’ve been thinking a bit about the postal system and wondering how/why people haven’t rebelled against such a burden if it’s so bad that the USPS has one out of five stars out of six thousand reviews even though it’s a public service.
You just simply send a random untrusted link. And we are currently VERY harsh on random links send here. If its youtube yeah of course we know its a video. A link to google yeah its a google. But a random link we as an admin dont want to check whats in there and we will just remove it, if we cant determine otherwise it. ( the link is just a java maven repository )
If its a common known website ( like youtube, instagram, imgur… ) then its all good not to say anything but if you do a neiche or a unknown link to a platform only few people know, it should be clarified where and what it leads to. In your case a forum post about a discussion about you and someone else.
You mean the USPS that can send a letter to anyone in the US, no matter how remote, for less than $1.
The USPS that has had its funding messed with for decades by Republicans trying to make private shipping the only option?
The USPS that is guaranteed by the Constitution to exist and provide services?
…
Yeah, let’s ditch this amazing service that provides stable union jobs everywhere in the US, and just let private industry take over, that works so well every other time we’ve done it.
You say that like I said anything about Republicans or privatization, if I may point out, that such low reviews from so many people come from only one demographic, and/or that something so basic or “stable” should be as forgiven as it is for stereotypical reports of internal mail theft, delivery error, heavy-handed monopolizing, and/or “going postal”.
The postal service ranks up there with public libraries, it’s a great service that needs to be preserved. Are you going to have individual points of failure at times? Yeah, my own postal person kinda sucks, but as long as it’s a system that relies on humans to perform it, that’s going to happen, but on the whole it’s a great service for what it provides on a daily basis.
Well, one might say the reviews constitute one point, a quirk like that isn’t born in a vacuum. Many of the “human errors”, if we may call them that, seem preventable if we include things like theft and the actual workplace. There are also so many tiny but impactful legal caveats (what actually constitutes mail fraud comes to mind) that it feels overpowering. If it were a private business, all this would be decried as an example of “monopoly syndrome”, heck Amazon (who I don’t respect any more) already has this criticism towards it.
Not really a recent thing, but the idea that supposedly if you travel faster than light, then you begin going back in time. But that doesn’t make sense to me. I guess the math has to work out somehow, but it seems to me that if light has a speed, then - ignoring the logistical issues related to having the power to travel ftl - travelling faster than light would simply be that, faster than light. Or to put it another way, if it takes 8 minutes for light from the sun to reach earth, then an object travelling 2c should take 4 minutes to travel the same distance, not negative 4 minutes or however that’d work out.
The only conclusion I can come to regarding how that works out logically, is that relativity sets the time light travels to “0” regardless of time taken, because that’s the only way I could see a negative value making logical sense. However it seems like that’d have its own issues, plus it implies that light instantly reaches its destination. Yet we know light has a speed and takes time to get places. It just… doesn’t make any logical sense. Yet I guess the math must work out otherwise scientists would have blown so many holes in relativity that it wouldn’t be used anymore.
inb4 “but causality…”
The speed of causality is inferred from the speed of light and the speed at which fields propagate in a vacuum. Causality, or the idea that cause must be observable before effect, is a human concept. Observing effect before cause doesn’t break causality, it only appears to do so because we’re seemingly limited to the speed of light. The reason why causality is said to have a speed (the speed of light in a vacuum) is because, with the exception of quantum tunneling, we’ve never observed anything that moves faster than light, so it’s a seemingly safe assumption to say that cause and effect play out at a speed no greater than light in a vacuum. Or to put it another way, the speed of light dictates causality, not the other way around. If something is found to be faster than light (like particles tunneling through objects), then causality must shift with it.
The speed of light is the speed of information, including gravity, electromagnetism, and some other things I am not thinking of off the top of my head. For example, if the sun disappeared right now, the lack of gravitational pull would reach Earth at the same time as it blinked out from Earth's perspective.
Gluons, the Strong Force. Quantum Chromodynamics. As massless particles, Gluons also move at the speed of causality, although popping in and out between Quarks and moving only very short distances.
They call it the speed of light, but the alternate term speed of causality is gaining traction. Maybe because it fits as the “c” in E=mc^2, where the “c” is sometimes referred to as “constant” but actually comes from the latin “celeritas”, which means “speed”.
The term “causality” is a nice fit-all more recent alternative.
What if you think of it this way. If the Sun exploded right now, we wouldn’t know for 8 minutes, but if you were to leave at the same time, at twice the speed of light and traveled for 8 minutes, you would be 24 minutes away from the explosion now.
So if you travel away from the earth and view it through a telescope, you would see back in time as you flew away, since the light traveling from earth wouldn’t be traveling as fast.
That’s not why relativity causes time dilation – it’s not the Doppler effect of light. If it were, then the direction of travel, not merely the speed, would be a factor.
Traveling toward an object would be forward in time since if you viewed it through a telescope you would be seeing the light sooner making it older faster.
No – as I said before, relativity isn’t caused by the Doppler effect of light. Direction of travel doesn’t matter, only speed.
The twin paradox occurs in a scenario where someone travels both away and then back. They still experience time dilation when they return to the starting point, though they’ve traveled the same direction away and back.
You don’t understand how relativity works. I’ve seen someone make the exact same error you did, about twenty years back, thinking that time dilation was a result of the Doppler effect of light.
It would be impossible for the aging effect to arise in the twin paradox if relativity were the Doppler effect of light because in that scenario, as in that case, there is the same amount of outbound and inbound travel.
Relativity effects show up when you have two different entities traveling at different speeds relative to each other. The direction of travel does not matter. One could be traveling toward, away from, or at right angles to another.
You’re trying to explain relativity just using Newtonian physics, which permits for the Doppler effect. Newtonian physics don’t provide for relativistic effects. That’s why relativity was such a big deal – because it explained behavior that was incompatible with Newtonian physics.
In actuality, you wouldn’t be returning to the same place, the earth has moved through space and time itself. So none of these theories work since neither could return to the same place. Thats why they are theories….
And again, your own wikipedia source has a Doppler section…. So you are now saying your own source isn’t correct?
First off, light isn’t just the fastest thing we know of, it is physically impossible to go faster than light according to the laws of physics as we understand it. This is because the speed of light is actually tied to the way spacetime works.
Imagine you are standing and you throw a ball. The ball travels at whatever speed you throw it, let’s say 5 mph.
Now, let’s put you on a train traveling at 20 mph and do the same thing. If you throw the same direction the train is traveling, your 5 mph adds to the train’s 20 and the ball goes at 25 mph according to someone standing next to the track. Throw it the other way and they see it travel at 15 mph. To you, in either case, it appears to move at 5 mph.
Light doesn’t do this. We’ve measured it, and in a vacuum light always appears to travel at the same speed (we call it c for short). If you hold a flashlight, your friend next to you can measure the speed of light and will find it to be c. If we put you back on that train and stand your friend next to the track, you will see the light moving at c, but so will your friend. Not c +/- 20 mph, but c. Even if we put you on a rocket traveling at some significant portion of light speed, say 0.5 c, both you and your friend would still observe the light from your flashlight to be traveling at c.
This is what Einstein figured out, and this is what we mean by Relativity. From this, we also know that objects moving faster experience an increase in mass (you have to get moving pretty close to c to really notice), and as you approach c that mass trends to infinity. That’s why anything with mass cannot achieve the speed of light, it would be infinitely massive, and thus require infinite energy to accelerate to that speed. Thus, only things with no mass (such as light) can move that fast.
That if there are infinite universes out there in the multiverse then there are infinite amount of universes exactly like this one. Which means we’re stuck living this exact life across infinite universe and we’ll never be able to escape it. So that’s kind of depressing but mind blowing I guess
Yep, if there’s an infinite number of parallel universes then there’s an infinite number where nothing is different. Maybe the only difference between the universes was the position of a mote of dust on an uninhabited planet in a galaxy on the other side of the universe.
If the many worlds interpretation is correct, that would mean that there's not really an infinite number of discrete realities, but more of a continuum. So there are infinite other realities in the same way that there are infinite points on a line, but this exact reality is still unique.
Infinite multiverse means infinite exact same universe as ours, yes. But it also means there are also infinite different universes. But you can use comparisons to see that there would likely be more universes that are different than ours because of small permutations in history causing larger effects in the future. So I like to think there are both many exact universes, and many very different universes.
What an enormous public heath issue iodine deficiency was in Switzerland and how completely everyone forgot about it after it was fixed by the introduction of iodized salt in the 1920s: www.lrb.co.uk/the-paper/v45/…/a-national-evil
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