Before You Crack Open Another Can--

[fry61]

-- this Christmas, ponder this.

 

Gravity can bend beams of light --- therefore photons must have mass.

 

Gravity reduction allows time to pass more quickly --- therefore does time have mass ??

 

May prove the old saying " Time drags when idle"

[Bob Tucker]

I firmly believe gravity increases once you retire.....

 

Why else would my scales show a bigger number now than 6 months ago?

[johnhetherington]

Of course gravity increases with time, that's why I keep finding it more difficult to get out of my chair.

[Derek]

Gravity has been pushing down on my head for a lot of years.

 

In fact so long I have started squishing out in the middle!!!

[WallerZ]

So to make the most of Christmas I should increase my gravity by eating lots of turkey?

And then when I get back to work, start inhaling helium to pass the time quicker

[agent_zed]

if you want something to make you wonder....

 

So gravity is a force that keeps planets in orbit, and can pull entire oceans about giving us tides....

 

yet if you get a fridge magnet you can overcome the entire gravitational force of the earth and lift a paper clip towards the magnet???

 

Also something that i find weird is that i can't actually 'see' anything, i can only detect the light that is bouncing off whatever it is i am looking at!

 

to understand everything is to understand we know nothing!

[Guest 2b cruising]

Gravity has been pushing down on my head for a lot of years.

 

In fact so long I have started squishing out in the middle!!!

In that case lie down a lot more for longer period.

Always put your feet up when watching the telly.

There might be a side effect though.

You could end up looking like a road roller has squished you out flat likes a pancake .

[Snapperpaul]

Space time is bent by gravity, light just follows the curve of space time

To the photons which have no mass they are traveling straight and true at the speed of light

As Einstiens theory of relativity states the speed of light is relative to the observer

Brian Coxs did a lecture with a torch whilst he sat on a moving platform

The camera on the platform showed the torch going up and down vertically in a straight line

For the stationary observer (the audience) the torch described a wave form as the trolley moved in front of them

[tractor]

And if you get into the gravitational pull of a black hole time speeds up so I keep away from them

[sj-bradley]

Snapperpaul is right.

 

Photons have no mass which is why they can travel at the speed of light. Also note that the speed of light depends upon the medium it is travelling in and is maximum in a vacuum.

 

Gravity is a weak force compared to the electromagnetic forces and nuclear forces which keep the nucleus of atoms together. This is why it takes a very large object such as a planet or star to create enough to keep planets in orbit.

 

Everything that has mass has gravity, so the more massive the object is, the more force there is between two objects. That's why the more massive or dense a particular object is, the heavier it is and the harder it is to move them too.

 

If an object is massive enough, it can become a black hole into which everything falls and even light cannot escape. Also, in a gravity well such as the surface of this planet, time passes at a slower pace than in free space.

 

Of course everyone knows that time is relative as it depends on which side of the toilet door you are standing (or sitting)

 

Physics 101 Astronomy and relativistic dynamics ...

 

Simon.

[sj-bradley]

And if you get into the gravitational pull of a black hole time speeds up so I keep away from them

 

Erm, no. The other way around. Time passes slower in a gravity well. The film Interstellar got this right.

 

I suppose that when you dig yourself into a hole, time indeed passes VERY SLOWLY for you... !

Edited December 15, 2015 by Simon B

[tractor]

Wot about the mortheus does time not become a loop

[sj-bradley]

Time is not properly understood at present, but it is known that it can only travel forwards in time.

 

Hypothetical time travel machines are really just that. It is possible to travel forwards in time, provided you travel fast enough.

If you can travel at (say) 95% of the speed of light out to a star which is 5 light years away, turn around immediately and travel back at 95% of c (light speed), you would have aged about 1 year, but your twin on Earth would have aged 10 years.

 

However, the amount of energy required to accelerate, stop and turn around would be immense.

 

That's also one reason why the moon landings can be proven to be true. Radio waves travel at light speed and require about 1.5 seconds to get to the Moon. That's why there was always this delay when Neil Armstrong answered simple questions. Also, anyone with an antenna pointed to the Moon would have picked up the messages directly and could pinpoint the direction they were coming from.

 

Conspiracy nuts overlook this obvious fact !

 

Simon.

[Guest 2b cruising]

I fink me drunk enuf tins now.

Now that is mass.

Edited December 16, 2015 by 2b cruising

[fry61]

If light (photons ) has no mass how come light falling ( attracted to ) a black hole cannot escape. AND Einstein calculated that light would be deflected by the gravitational pull of massive bodies ( planets) --this theory was proven by observing transits of star light when the star passed behind the sun during a total eclipse.

 

Or is it due to light being an electro-magnetic wave ?

 

Time to finish the Grouse & go to bed