EPTAsk and answer stupid questions here! - Page 156
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Tapioca Weasel
81 Posts
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Orcasgt24
Canada3238 Posts
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Zess
Adun Toridas!9144 Posts
On October 20 2014 09:45 Acrofales wrote: Okay, fair enough, but if the observable universe is a sphere with a radius of 13billion light years, but the true dimensions of the universe are wildly different, then the density or type of stuff we can see should be different in some directions, right? For instance, if we're not in the center, then if our horizon is 13 billion light years, shouldn't the galaxies at one side be younger than the other? Unless our sphere of observable universe happens to. be in the center of the actual universe. In fact, isn't the fact that we are able to see that there seems to be nothing in any direction one of the main arguments for the age of the universe? You can't say that the first stars formed approx 13 billion years ago, because whatever direction we happen to look in, that is the oldest star we see, and if we look further away, and thus further back in time, there is nothing, and simultaneously hold that the observable universe is not the entirety of the universe, and there is some mysterious reason X that stops us from seeing further than. 13 billion years away. Obviously the fact that everything is moving away from us at the right speed for the universe to have started 14-billion years ago can be combined to say that whatever is beyond the visible limits of the universe is not something we'd recognize as our universe; but then we're back to the originall issue: we seem to be at the center of this expanding bubble that we do recognize as our universe... To (over?)simplify, parts of the universe are moving away from us faster than the light can get back to us. So we have no idea what is happening out there. But from the observable universe, there is no way to tell where the center of expansion is because the expansion is like a uniform expansion of a metal plate. From the perspective of any particle on a heating plate, you would be the center of expansion because everything is moving away from you. And the analogy continues: it doesn't really matter what the "shape" of the universe is. A torus or a star shaped piece of metal still expands uniformly: if you head a metal ring the center of the ring doesn't constrict but the whole ring expands. The obvious disclaimer for all science analogies applies here: while the observable effects in the two specific examples are similar that doesn't mean that one mechanism is a drop-in explanation of the mechanics of the other. | ||
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ZenithM
France15952 Posts
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Mordanis
United States893 Posts
On October 20 2014 10:54 Orcasgt24 wrote: Is the universe round or flat? Nothing is truly infinite so it must end where or be round! This is a very difficult question to answer. First off, the statement "Nothing is truly infinite" is sort of a philosophical assumption, and there are several people who would disagree. But on to the actual shape -- Relativity implies that the universe is made of 4 dimensions (3 space + time, screw strings :D). According to the Big Bang Theory, the universe was at one point infinitesimally small, and it was in this configuration at a definite time. It then began expanding, and still is (in fact, its expanding more rapidly than ever!). Now, If the dominant forces in the universe are expansionary (dark energy and other stuff we don't really understand, but they make our models work right), the more the universe expands, the faster it will expand. It will never contract, and so will keep expanding (it will go towards infinity). If the dominant forces are contractionary, eventually the universe will stop expanding, contract, and go back to a very small point. The two could be balanced perfectly, and if they are, the universe will still end up going towards infinity. In 4 dimensional spacetime, the first and third scenarios are infinite (since time is a dimension and you can always keep going further in time). The second, however, is finite. Cosmologists would call the shape of the universe in that case hyperspherical, which is the 4 dimensional equivalent of a sphere. If you're interested or confused, here's a wikipedia article to explain more about the shape. | ||
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FiWiFaKi
Canada9859 Posts
On October 20 2014 12:48 ZenithM wrote: Can I access my entire post history on TL? Or just the last 50 posts? You can search your name in the sidebar to see the latest 1000. That's the best I know how to do though. | ||
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d_runk
124 Posts
(My dream was, as I posted in this thread many moons ago a red nike SKT sweatshirt -but I guess that ship has sailed with NB being the new sponsor - , but I'd also like the grey CJ jacket - Scotland, despite the awesome summer is back to its normal rainy-grey self again  ) | ||
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Orcasgt24
Canada3238 Posts
+ Show Spoiler [image] + ![[image loading]](http://i.imgur.com/RC8mcob.jpg) | ||
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icystorage
Jollibee19349 Posts
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Epishade
United States2267 Posts
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Simberto
Germany11519 Posts
Disclaimer: I am not a doctor, nor do i condone eating people. | ||
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miky_ardiente
Mexico387 Posts
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rebdomine
6040 Posts
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Tephus
Cascadia1753 Posts
On October 22 2014 11:53 miky_ardiente wrote: why sometimes when i start my car the acceleration meter is already at 1.5 ? shouldnt it be 0 since my car is parked and not moving? or acceleration 0 doesnt exist ? Can you clarify? Most cars don't display acceleration, they have a speedometer and RPM meters (along with fuel meters and battery meters). Cars RPMs will typically idle from 600-1000, which might look like .5 or 1 on your meter if you ignore the x1000 on it. RPM is just a measure of how fast the engine is spinning though, and when you start your car, the engine spins, even if you aren't moving. | ||
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ComaDose
Canada10357 Posts
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3FFA
United States3931 Posts
When was the first jerk? (adjective, NOT the verb) | ||
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Yoav
United States1874 Posts
On October 23 2014 01:14 3FFA wrote: Where did the three little pigs get their knowledge of architecture from? When was the first jerk? (adjective, NOT the verb) 1. The 3 little pigs: From architecture school. + Show Spoiler + All the civil engineers in the audience went wild at that one, I promise. 2. Jerk as an adjective: First jerk as an adjective... well that rules out people who are jerks (who have existed since the beginning of human existence), as well as jerking off (also probably since the beginning of humanity). So let's talk about jerk spice, which gives you jerk chicken and the like, where jerk is in fact used adjectivally. Jamaican jerk spice came into use after 1655 when the British invaded the Spanish colony of Jamaica. Many of the inhabitants (at this point largely African slaves) took the opportunity to win freedom by fleeing into the mountains. There they mixed culturally with the local Tainos and developed what we call Jamaican jerk sauce, which enabled the creation of jerk-spiced foods and the use of jerk as an adjective. | ||
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frogrubdown
1266 Posts
On October 23 2014 02:19 Yoav wrote: 1. The 3 little pigs: From architecture school. + Show Spoiler + All the civil engineers in the audience went wild at that one, I promise. 2. Jerk as an adjective: First jerk as an adjective... well that rules out people who are jerks (who have existed since the beginning of human existence), as well as jerking off (also probably since the beginning of humanity). So let's talk about jerk spice, which gives you jerk chicken and the like, where jerk is in fact used adjectivally. Jamaican jerk spice came into use after 1655 when the British invaded the Spanish colony of Jamaica. Many of the inhabitants (at this point largely African slaves) took the opportunity to win freedom by fleeing into the mountains. There they mixed culturally with the local Tainos and developed what we call Jamaican jerk sauce, which enabled the creation of jerk-spiced foods and the use of jerk as an adjective. 'Jerk' is being used as a modifier in a compound noun there; that doesn't make it an adjective. Hence: (A) That spice is a jerk. (B) #That spice is jerk. edit: Note that the other 'jerk' noun can be used as a modifier as well, as in, "I would have gotten away with it, if it weren't for those jerk cops". English is pretty promiscuous with using nouns as modifiers. | ||
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miky_ardiente
Mexico387 Posts
On October 22 2014 13:20 Tephus wrote: Can you clarify? Most cars don't display acceleration, they have a speedometer and RPM meters (along with fuel meters and battery meters). Cars RPMs will typically idle from 600-1000, which might look like .5 or 1 on your meter if you ignore the x1000 on it. RPM is just a measure of how fast the engine is spinning though, and when you start your car, the engine spins, even if you aren't moving. yes thanks i was reffering to the RPM meter....my knowledge of cars is 0 | ||
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3FFA
United States3931 Posts
So, when was the first jerk (Noun or Adjective)? Why would civil engineers laugh at that architecture school joke? | ||
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