1. ## geordief

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2. ## studiot

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3. ## NimrodTheGoat

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4. ## Rob McEachern

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## Popular Content

Showing content with the highest reputation on 12/31/17 in all areas

1. 2 points

## Time and speed and how speed impacts time

You have to be careful here (and in Science generally) since this has more than one meaning. For any observer time passes normally for herself. She just witnesses it passing differently for others who are travelling at (any) speed relative to her. If they are travelling at the same speed together, however great, no effect will be witnessed. The relative speed is zero. The any effect observed will depend on the relative speed and is so small at to be unobservable at low relative speeds. That is why we say there is an effect at high relative speed. Does this help?
2. 1 point

## Time and speed and how speed impacts time

Excuse my ignorance first of all. I'm just a guy who never really paid attention in any science class, but now, a bit later in life, I've become very interested. So, (and I may even be starting from a poor understanding) but from what I get, speed, especially light speed, if you're travelling at that speed, has an impact upon your experience of time. Before I go any further, just want to be sure I have that right!
3. 1 point

## Expansion and Inflation

Space between non gravitationaly bound objects such as galaxies increases with time. I have read about the consequences of this phenomenon but not so much about the phenomenon itself. It permits objects to recede from one another at speeds higher than c,I think. Is this speed as seen from a third frame of reference or also from that of one of the objects in question? If the latter is true does that imply that these objects are (never were) not connected in the causative sense? Also ,is Inflation similar to Expansion (differing in degree and circumstance as it were) or are they completely different animals?
4. 1 point

## Time and speed and how speed impacts time

What I found hard to accept was that both parties saw the others' clocks (and general movements) as slower than each others' . Also bizarre was the finding that when the mutually moving parties were reunited the time difference accumulated did not disappear to zero. So no "optical illusion" ,but a stark reality born out by experimental observation.
5. 1 point

## Expansion and Inflation

I didn't realize GR could\did model the expansion of the Universe. Are we getting into "Einstein's greatest mistake" territory?
6. 1 point

7. 1 point

## Space a constant, singularities all over the universe

Are you sure? Everything I have read suggests that dark matter has been around as long as matter. One of the lines of evidence for dark matter is the cosmic microwave background (CMB) and that is a lot more than 10 billion years old. The Big Bang model is not an explosion, and certainly not an explosion of matter from some central point. Well, it has. And it is space that has expanded (not matter exploding into space). Space is not made of anything. It is just the distance between things. Which is affected the presence of mass - the effects of this include the thing we call gravity. I don't know if that is true. Everyone agrees we can't know. I don't know what proportion think it is infinite. People pop up on science forums insisting it is impossible for it to be infinite and impossible for it to be finite with about equal frequency. I have never seen a survey of physicists, though. It wasn't an explosion into anything. The universe was once entirely full of hot, dense matter (plasma). The universe expanded and, as a result, the matter cooled and gravity caused the gas to clump into stars and galaxies. There is no "outside". Note that a singularity means that the theory no longer applies at that point - a bit like dividing by zero. There are many variations of the basic Big Bang model. Some of these suggest multiple Big Bang "events" (inflation and expansion) producing multiple universes. These ideas are not really testable but are a natural consequence of the mathematics. For example: https://en.wikipedia.org/wiki/Eternal_inflation However, the universe we can see came from a single Big Bang event. That doesn't work. If there is an even distribution of matter around the universe (and it would have to be evenly distributed because expansion is the same in all directions) then it will have no net effect - the matter pulling to the left will be exactly counterbalanced by the matter to the right (and so on for all directions). Newton proved this a long time ago! That almost certainly won't happen. Nearly all of the matter in the galaxy will continue to orbit without being affected by the black hole (which only makes ups tiny amount of the matter in the galaxy). The gravity of black holes behaves just like any object of similar mass. One the gas and stars around the black hole have been absorbed then there will be nothing else for it to absorb. Actually, you can treat gravity as space falling into a body like a black hole: http://jila.colorado.edu/~ajsh/insidebh/waterfall.html But that's OK because space is not made of anything so it isn't really disappearing or being used up. Not only suggested, but it has now been observed several times. Exciting stuff. This can only happen if the black holes are in orbit around each other. It is a pretty rare event.
8. 1 point

## Look at this manderine

Found it while I was working. A deformation on the side of the manderine. It is weird, looks like it wanted to grow a branch of its own. I named him Morangê.
9. 1 point

## Could the laws of physics have been different in the past?

The video interviews on "Closer to Truth" give a number of well-known and Nobel Prize winning physicists' answers to this very question. Here is the summary, introducing the interviews, on the topic "Are the Laws of Nature Always Constant?": Summary: "The laws of nature or physics are assumed to be everywhere the same, on the far side of the universe as sure as on the far side of your house. Otherwise science itself could not succeed. But are these laws equally constant across time? Might the deep laws of physics change over eons of time? The implications would be profound." Here is the link to the video interviews: https://www.closertotruth.com/series/are-the-laws-nature-always-constant
10. 1 point

## Could the laws of physics have been different in the past?

He's a creationist and is manipulating physics concepts to peddle his agenda. The constants that govern nuclear structure had to have been constant or fission either would not have happened, or given the products that it did. We can check spectra from distant stars and see that the coupling constants relevant to those interactions have not changed. We can do precise measurements over some interval to show that the constants are currently not changing. Typically this is the fine structure constant.
11. 1 point

## Laptop battery, how to increase life of

To optimise battery life, the ideal usage range is between 20% - 90% charge. Topping it up from any point above 20% is best. Don't fret about running it down to that number, just keep it above it. Keep it plugged in when you are using it and there is wall power available. Just use it as a portable device when it's necessary. I don't know. Edit: I don't think so because it's running off the mains when plugged in. Once the battery is charged it won't draw current again until the voltage drops below a certain point.
12. 1 point

## Is cancer a side effect of our evolving so quickly?

What evidence leads you to that conclusion?