What would be different if light did not travel in a straight line?

Answer 1

simple.. there will be no life.

It will be dark.

While true it would be dark, don't tell the many thousands of organisms hanging around hydrothermal vents at the bottom of the oceans [where there is no light] that they aren't alive.

Answer 2

If light does not travel in a straight line, vision would not be accurate since objects will appear to be in different places. The reflected light that hits the eyes will bring images from different areas.

Answer 3

Light doesn't always travel in straight lines. It bends and changes direction for a number of reasons. The most common reason is refraction when light travels in transparent media of different density, as in lenses, or in the atmosphere, or as it passes from water to air.

The effect of curved light paths is that the object you see is not actually where you think it is. This makes spearing fish in shallow water very difficult, as the fish is not where it looks like it is.

Gravity also bends light, but the effect is negligible in normal life.

Black Holes are collapsed stars with gravity so strong that light they emit curves back into them, so you cannot see them - hence the name.

Answer 4

Technically, the answer to this is "no". Einstein's theory of relativity proves that light is curved by the force of gravity. However, the curvature is very slight over most of the vacuum of space, so it is usually safe to treat it as a straight line.

Answer 5

As a matter of fact, it doesn't always, especially here on Earth where it has to

travel through air.

Light curves as it makes its way through air. The effect is small, noticeable only

over long distances, but it's the reason why, within a few hundred miles of a large

mountain, its peak can occasionally be seen up in the sky. It's also the reason

that the stories of flying horses and magic carpets, and reports of palm trees seen

hanging in the air, come from places near harsh deserts, where the air is dry, the

temperature swings are extreme, and large vertical gradients of atmospheric

refractivity are common.

Light almost always curves gently downward as it travels through air, and the result

of that is to make distant objects appear to be higher than they actually are.

Whenever light doesn't travel in a straight line, things appear to be located in

the wrong direction. That's why the end of the straw that's down in the drink

looks as if it doesn't line up with the top end, and why you can still see the sun

above the horizon for several minutes after it has actually set, and why it looks

like your face is behind the mirror.

It's also the reason why the fish in the shallow creek are not where they appear

to be, and why you and I fail miserably when we try to catch one with our hands.

But fisher birds, bears, and spear fishermen very easily learn to adjust, and that's

exactly what we would do if the curvature of light were much greater. Our brains

would learn where things really are based on where they appear to be, and we'd

correct for it subconsciously, without ever thinking about it.