How Fast Do We Perceive Light Compared to Its Actual Speed?

In summary: However, the brain can compensate for this and make things appear to be happening in real time. So, while the speed of perception may not be as fast as light, the brain can make up for this and create the illusion that it is. In summary, the human brain is able to compensate for the slow speed of neurological processes and create the illusion of perceiving things at the speed of light. The flicker in TVs and the perception of objects moving quickly are all a result of this compensation. The brain is able to fill in the gaps and make things appear seamless, even though the speed of perception is much slower than the speed of light.
  • #1
dcclxxvii
6
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If nothing can travel faster than light.Then i am confused as to how i am able to perceive light seemingly the instant i open my eyes.Is the speed at which i can perceive comparable to that of light?Shouldn't the matter withwhich my brain is constituted not significantly impede the electromagnetic radiation as is received via the retina,optic nerve and receptors of my brain

Any suggestions and commentary would be apprecaited.
Thanks :confused:
 
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  • #2
Light traverses a metre in a few nanoseconds. A TV only updates the picture every few milliseconds, and even that is too fast for you to notice the flicker.
 
  • #3
Remember that you're seeing light that's already at your location, so the speed of it doesn't matter. For instance, if you open your eyes at night and see a star, that light has been traveling for thousands of years. It just happens to be hitting your eye at that moment. Neurological processes are indeed very slow compared to c, but the brain compensates. A lot of things move too quickly for you to actually see them properly, but the brain fills in the blanks. A baseball batter, for instance, cannot track a fastball from the pitcher's hand to the plate. Some watch it leave the hand and extrapolate where it will go, and others wait until it's close before acquiring a picture of it. To both types, however, it appears to be a constant scene.
 
  • #4
Also, yes, the "speed of perception" is extremely slow comparatively. For continuous visual cues (ie, watching a computer animation), you can notice changes over perhaps a hundredth of a second, but the initial information takes somewhere on the order of a tenth of a second to get from your eyes to your brain.

The slowest part of turning on a light is probably the time it takes to heat up and start emitting light, but that is probably only a few miliseconds. The light itself takes only 1/3*10^9 seconds to get from the light to your eye if it is a meter away and the signal from the switch to the light not much more.
 
  • #5
These are all very comprehensive responses.I probably should have presented the inquiry in a more stereotypical hypothetical format.I agree,i cannot follow with my eyes a baseball traveling at a velocity of over 80mph.As well,i witness no flickering as i am watching an television broadcast.However,assume i could perceive,not conceptualize,at near 286,000mps,and i do not mean to say,move my eyes at this velocity.Would i then be enabled to see this flicker on my television as it updated? Being that perception in this assumption is observing at a velocity relative to that of light.Would there be any frame of reference that would indicate any change?Would not all that i observe seem as usual?

Thank you for your answers
 
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  • #6
dcclxxvii said:
These are all very comprehensive responses.I probably should have presented the inquiry in a more stereotypical hypothetical format.
I don't know about that. A little clarity would help though.

AM
 
  • #7
cesiumfrog said:
A TV only updates the picture every few milliseconds, and even that is too fast for you to notice the flicker.
I notice the flicker. This is a combination of the persitance of the phosphors on the TV and a person's eyes. I can't stand monitors at 60hz. I run mine at 85hz. The TV phosphors are pretty much set for 60hz, so the main variation is your eyes, and how bright the room is.

The flicker is less noticable in a dark room (like a theater running at 24 frames per second), because the persistance of a persons eyes is longer under these conditions (dark background, relatively bright screen). As an extreme example, in a very dark room, flashing a strobe will cause an image that persists for several seconds. In my case, I turn down the lights when watching TV to reduce the flicker effect.

Getting back on topic, the speed of impulses in your nerves and brain cells is a lot slower than the speed of light. What you interpret as instant, is really hundredths of a second.
 
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Related to How Fast Do We Perceive Light Compared to Its Actual Speed?

1. What is the speed of light and how is it measured?

The speed of light is a fundamental constant in physics, denoted as 'c'. It is defined as the speed at which light travels in a vacuum, which is approximately 299,792,458 meters per second. This value is determined by measuring the time it takes for light to travel a known distance, usually using highly precise equipment such as lasers and mirrors.

2. How does the speed of light affect our perception?

The speed of light plays a crucial role in our perception of the world around us. It is the fastest speed at which any information can travel, which means that all the visual information we receive reaches us at the speed of light. This allows us to perceive objects and events in real-time, giving us a sense of the present moment.

3. Can the speed of light be exceeded?

According to Einstein's theory of relativity, the speed of light is the maximum speed at which anything can travel in the universe. This means that it cannot be exceeded by any object or particle, regardless of its mass or energy. Many experiments and observations have confirmed this theory, making the speed of light a fundamental constant in our understanding of the universe.

4. How does the speed of light influence our understanding of time and space?

The speed of light has significant implications for our understanding of time and space. According to Einstein's theory of relativity, time and space are relative and interconnected, and their measurements are influenced by the speed of light. This means that as an object accelerates and approaches the speed of light, time and space become distorted, and the perception of time may change for the observer.

5. Is it possible to travel at the speed of light?

As of now, it is not possible for any object with mass to travel at the speed of light. According to Einstein's theory, the closer an object gets to the speed of light, the more its mass increases, making it impossible to reach the speed of light. However, scientists continue to explore ways to manipulate space and time to potentially achieve faster-than-light travel in the future.

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