Category Archives: technology

Does Time Exist?

There is no question that we experience what we call time.   There is a precision with which we can measure the progression of events over time that is phenomenally accurate.   Things age and particles decay over “time” and it is consistent.    However, physical laws that use time as a reference work equally well for time reversal - going backward – a particle hitting another particle, generating other particles and emitting photons will work just as well running backward according to physics.   We just have never experienced time reversal and this disconnect with the laws of physics seems to be a mystery.  This disconnect is used by many to express the opinion that time exists.   However the fact remains that equations of space and time break down at certain points and time falls out of some of them as an unnecessary factor.

Think of this: photons live in “null” time.  They live and die in the same instant because they travel at the speed of light and therefore if time exists for them, they do not experience it.   They experience zero flight time over zero distance no matter how far apart the start and finish line are.  They live in a go-splat world.    A photon leaving a star a billion light years away destroys itself in our eye the instant it is emitted, having not aged even a fraction of a nanosecond in its long trip.   Space and time are that warped!

The space and the time have been warped because of the speed of the photon.  It travels at the speed of light.   Our very definition of speed involves time so when we say the speed of light we assume that time exists, but for the photon time does not exist.  

A photon experiences zero distance and zero time due to its incredible speed.   Every photon that lights our office or illuminates our book arrives the instant it is emitted.  It has not aged even though we can calculate that it moved from the bulb to our book and then to our eye at about one nanosecond per foot of travel.  The photon did not experience the “time” that we measure or calculate.  It aged not at all.  Time does not exist for any particle moving at c.  It only exists for us as calculated or measured in a laboratory.  But does it exist as a real dimension?  Does it have a physical basis?  

A photon in flight between point a and point b is invisible to any and all observers.  It does not exist in flight and can only be detected at b when it actually arrives.   The photon in flight experiences null time – time zero – no time – non-existent time, and travels a null path – or no path at all, regardless of the length of its travel.   Time for the photon does not exist, nor does distance.  Those measurements of time and distance for the photon are for our domain only – the human one.

Now consider an extension of that thought – most of the particles that make up our world vibrate and exchange energy with each other.  That occurs even at temperatures close to zero.   There is also a froth of virtual particles that pop into and out of existence continually at all times even in a so-called perfect vacuum.     All the energy exchanged through photons is timeless because all photons are moving at c.   Even gravity moves at c.  Gravity is also timeless within its self.   The exception is for atoms that bump into each other and exchange energy through vibration and bumping.   Or do they?   Do they actually touch or isn’t there an exchange of particles  moving at c that keep them apart?

If the energy transfer by photons is timeless, the photons are timeless, gravity is timeless all due to the speed of light as experienced by the particles that carry them, then does time exist or are we merely measuring external events by counting uniform progressions that we experience and can see?

I know and acknowledge that we can measure the speed of a photon to a very high precision.  I know that we can measure the speed of gravity as other planets tug on ours and on each other.    The measurement is based on the progression of the components of our clocks.   We do live in a dimension that experiences progression of events in one direction which we call time.  

However, we can measure but we cannot see.  We can observe the effects but not the event.   The truth is that whenever something is traveling at c, simultaneous observations are impossible.  Every observer of the same event sees something different.    Have you ever seen time?  Maybe the change in a clock, which is actually only a measure of repetitive events, whether a wind up (measuring escapement events) or a NBS clock counting cycles of an atomic nature, but not timeWe can’t see time, only experience it.  We can’t measure time, only define it.

Time for us may be just a projection of ourselves on a line defined by a progression of events that occur in a uniform manner, but it may not really exist.    We are bundles of energy made up of atoms and particles in extraordinarily rapid motion.  Take us down to the quantum world and we are made up of many quadrillions of particles exchanging energy among themselves in mostly empty space.    In such huge numbers there is an average motion and an average progression of events that may make up our concept of time.  Certainly our most accurate “clocks” are merely counting cycles of an atomic nature.   Even the National Bureau of Standards admit they are “not measuring time, but only defining it“.

Does time exist just for us because we experience this progression in a uniform manner? Perhaps it is not actually an extra dimension as we have been so often told.

Do you think time exists as a dimension in the same manner as x, y, z?  Is time real?  If you have been following my last two posts, you will understand it is the lack of time, at least on the photon level, that explains quantum weirdness.   And explains it well.

What do you think? 

Oldtimer

PS:  here are some other articles by Oldtimer on the subject of time

Enjoy!

Quantum Weirdness – A Matter of Relativity? Part 2

Quantum Weirdness

A Matter of Relativity? 

 

Copyright 2006/2007 James A. Tabb 

Part 2 – Double Slit Weirdness

When a proper light source (coherent – light from a single source all at the same frequency) is placed in front of a screen with a narrow slit, the light is diffracted (spread out) as it goes through the slit and appears as a shaded band centered on a screen or photographic film. The light is scattered and/or bent by the edges of the slit as shown in Figure 3.

Single Slit Diffraction
Figure 3. Single Slit Diffraction

 If we add two more slits located side by side between the first slit and the screen, the light passing through each of the new slits is diffracted again such that the photons from each slit are bent across each path and combine to reinforce or cancel each other where they strike the screen.

 Double Slit Diffraction

Figure 4. Double Slit Interference

The result is an interference pattern (light and dark bands) on the screen as shown in Figure 4. If you block either of the two middle slits, the interference pattern disappears. If a photographic film replaces the screen and the intensity is reduced so that only a few hundred photons are sent through the double slits before the film is developed, the interference pattern will be made up of individual dots organized in a pattern that duplicates the interference pattern. Keep the film in place long enough and the patterns become more complete. Put a cover over one of the slits and the film still shows dots, but no interference pattern, only a diffraction band. Put a detector in one of the slits and the interference pattern also disappears.

Now if the light source is reduced in intensity enough to send only one photon at a time, a weird result can be seen if the photographic film is left long enough (days or even months in a very dark box) where both slits are left open. The interference pattern continues to develop on the film, even though there is no possibility of interference (or even photon bumping) unless the individual photons go through both slits somehow.

Part of the current explanation is that the photon goes both ways, but any measurement (putting a detector in the path) always disturbs the measurement. In fact a whole class of quantum theory has developed around the inability to make precise measurements due to the measurement disturbance problem. How do we explain this quantum weirdness?

A Matter of Relativity

There are two processes going here. One process is the real time that our experimenter sees, about 1 nanosecond per foot of photon travel. The photon is traveling through the experiment with real and measurable delays from the emitter to the first slit and from there to the double slits and from there to the film. The other process is that the photon’s relativistic path is zero so it is in contact with the film and the emitter at once and all of its paths in between are of zero length and require zero time. All paths that can lead to the same path are conjoined. Time of flight and distances for the photon expand only as it passes through the setup. The photon and the observer see simultaneous events differently. All the events are simultaneous to the photon, but none are to the experimenter.

All the elements of our experiment have no depth and seem to be congruent as if they were paper cutouts that have been bonded together with the emitting source. As observers, we can’t see it. As the photon leaves one element of our experiment, such as the first screen with one slit, the double slits are squeezed down to a point and plastered across its nose. The photon easily fits across both slits of the second screen as the distances to them are zero and thus the distance between them is also zero. Indeed it fits across the entire second screen, but the edges are less distorted. Since the photon is also plastered across the slits, everything behind the slits is also plastered there – the entire path is available at one instant as in Figure 5 a. The photon is able to take all paths (even simultaneously) that lead to a common point because they are all in front of it as it enters our experiment, and zero distance separates all the paths. No amount of fiddling with flipping mirrors or detectors will fool the photon into disclosing its path because the mirrors and detectors are also plastered to the photon’s nose throughout its (instantaneous) flight. The mirrors and detectors are in place when the photon makes its decision or they are not. The result is path shut or open.

As the photon moves from the first screen to the second, the second screen moves with it (attached to its nose) until it reaches its normal (real world as we see it) dimension and then expands as the photon moves into the slits as in Figure 5 b. Portions perpendicular to the path of the photon become normal size and atoms from the edges again buffet the photon.  Everything behind the photon is of no consequence, gone – vanished.

Relativistic Double Slit

Figure 5. – Relativistic Double Slit

 From the relativistic point of view, the photon has a number of crisis points such as within the first slit. As it passes through the first slit, the atoms at the edge of the slit buffet it and the photon’s path is randomly diffracted from the original path.   The slit has grown to normal size (perpendicular to the photon’s travel) but now the photon is virtually attached to the entire screen containing the double slits in the background that represent the next crisis point or wakeup call. If neither slit is blocked, it has an opportunity to go through both.

Photon Recombining

Figure 6. Photon Recombining

I see the photon as being a packet of energy that obeys the laws of conservation of energy. It flows around the barrier between the two slits only if it can recombine on the other side without ever completely breaking into two separate pieces. It behaves almost like a perfect fluid and leaks through where it can, but unlike a perfect fluid, it cannot separate into multiple “drops”.

If the packet can meld behind the slit spacer as in figure 6, it does so before it separates in front of the spacer. The melding process takes place an integral number of wavelengths from the slits and results in a change in path that leads to an impact in the interference pattern, a pattern that can be calculated using the methods of QED.  As soon as the melding takes place, the photon separates in front of the slit spacer and begins joining the rest of the body already melded together, so that the photon is always a full packet of energy

If melding does not take place because of a blocking detector or some other shield, then the photon pulls itself into whichever slit passed the bigger portion of its packet and slips through that slit whole.  If it is the blocked slit, it is destroyed there.  If it is the unblocked slit, it comes though whole but does not interfere with itself because it did not meld around the slit due to the blockage in the other slit.  It may also be destroyed by the slit itself.   The photon is destroyed in the blocked slit or on the film behind the open one, never both. It makes no choice. In the case of a blocked slit, there is no recombination. The side with the larger energy pulls the photon through an opening if there is one and if that opening has a detector or blockage, it dies there.

The answer to the weirdness of photons seeming to interefere with itself is that it is due to the forshortening of the experiment due to the effects of relativity.

Next:  Polarized Light Weirdness Explained

Quantum Weirdness – A Matter of Relativity? Part 1

Quantum Weirdness

A Matter of Relativity?

Copyright 2006/2007 James A. Tabb

Part 1: Introduction and Photons In Glass

Quantum Electrodynamics (QED) theory has developed to be the theory that defines almost all of the understanding of our physical universe. It is the most successful theory of our time to describe the way microscopic, and at least to some extent, macroscopic things work.

Yet there is experimental evidence that all is not right. Some weird things happen at the photon and atomic level that have yet to be explained. QED gives the right answers, but does not clear up the strange behavior – some things are simply left hanging on the marvelous words “Quantum Weirdness”. A few examples of quantum weirdness include the reflection of light from the surface of thick glass by single photons, dependent on the thickness of the glass; the apparent interference of single photons with themselves through two paths in double slit experiments; the reconstruction of a polarized photon in inverted calcite crystals, among others.

This paper introduces some ideas that may explain some of the weirdness.

Photons and Relativistic Effects:

I suggest that most of the difficulties we have in addressing the various weirdness phenomena at the particle level can be traced to relativistic effects. It all comes down to the two different simultaneous viewpoints: The one we can see and measure, and the one the photon experiences. Relativistic effects rule the photon world and our life experiences rule ours.

Consider that photons travel at the speed of light and thus experience relativistic effects. What are these effects? Einstein gave us some tools to work with to describe the various space-time relativistic changes as shown in Figure 1. There is a mass equation also, but the mass increase is not a factor here, since we know that the photon has no rest mass.

Relativistic Equations

Figure 1.   Relativistic Effects at c

The photon’s clock stops because the time between clock ticks becomes infinitely long at c. Similarly, the distance traveled becomes zero because the photon’s unit inch becomes infinitely long and stretches to the end of its journey in one bound. In other words, the entire path is foreshortened to zero length, and everything in its path is compressed to a dot.

We, on the other hand, see the photon from our experimental perspective. Photons move at speed c, take a nanosecond to go about a foot, take centuries to go from a nearby galaxy to earth, all of which we can measure or calculate with confidence and confirm with experiments.

The Photon’s Go-Splat World

The photon lives in a “go-splat” world. The clock of a photon completely stops the instant it is emitted and stays stopped throughout its journey. The distance traveled by a photon becomes zero as compared to the distance measured by the stationary observer. It may take a photon a billion years to cross from a distant galaxy to our telescope from our perspective, but for the photon, as soon as it is emitted, it arrives – splat; there is no time elapse in the photon world. In effect, the space and time between the photon’s emission and its destination are severely warped.

Therefore, the photon’s world is flat and stapled together, front-to-back, between its start point and its end point. In effect, the photon is touching its emitter on one end and our eye on the other with zero depth of field. Whatever phase it has at the time of emission, it has when it hits our telescope because it is all frozen in time. Physicists call the time experienced by the photon null time and the path the null time path.

It is this stapled together, zero time world that I believe explains much of the quantum weirdness we experience. Our life and experimental experiences are so strong that we can’t easily get our minds around the relativistic phenomena.

What the photon would know of the experimental setup, whatever it is, consists of wake-up calls at various edges or medium changes and eventually wherever it is absorbed in our screen or detector, all zero distance apart. This is vastly different from our perspective where everything is so carefully laid out, separated, calibrated with finite distances and photon flight times.

From our perspective, if it is going across a table, it moves about a foot every nanosecond. If it is going across the universe it takes years, even millions or billions of years to get from there to here. However we see it or calculate it, the time it takes for the photon’s lifetime is always zero. Go-Splat! As soon as it leaves on its journey, it arrives.

Quantum Weirdness in Glass

One of the weird aspects of photons involves reflection from glass of varying thickness. Send a laser pointer beam perpendicular to a pane of glass and about 4% of it will reflect back, on average, but, by carefully selecting glass of various thicknesses, the reflections vary from 0% to 16%. Glass a foot thick can be slightly adjusted in thickness to not reflect at all! All the light goes into the glass – perfect transmission. QED easily shows how this works for light beams. Rays from the back of the glass interfere with the rays coming in the front so as to cancel the reflection if the wavelength is a multiple of ½ wavelength.

However, the cancellation at ½ wavelength also works for individual photons for thick glass, and there seems to be no answer other than “quantum weirdness”. How does an individual photon know how thick the glass is the instant it hits the front surface when the back surface is thousands of wavelengths away? The reflected photon would be six feet away before a copy could make a round trip through a foot thick piece of glass. (Two feet round trip at 1/3 speed of light in air)

Quantum Weirdness and Relativity

Lets look closer at our foot thick piece of glass. The photon is moving at c and from a relativistic perspective our piece of glass has zero thickness (our entire experiment has zero thickness) as shown in Figure 2a.

Photon in thick glass

Figure 2. Photon in Glass

Immediately after impact, a full  half wave of the photon fits completely into the glass (2c), no matter how thick. The photon’s wavelength in glass is only 1/3 of its air wavelength. If the thickness of the glass is a multiple of a half-wave of the (shortened) photon, the photon will go right on through without reflection. Otherwise, depending on the thickness, some percentage (0 to 16%) of them will reflect.  In effect, the glass collapses to zero thickness if it is an exact multiple of the half wavelength, and if not, there is an overhang on one of the collapsed thicknesses that determines the probability of reflection.  Thus the photon does not have to “wiggle” its way to the far side and back to make its decision. If it is going to reflect, the decision is immediate due to the glass being foreshortened to fit the photon. It is, in fact, relativistic foreshortening of the glass.

Note, although the surfaces in the drawing above and those that follow are drawn with straight lines and flat, they are shown that way only for illustrative purposes. At c, all the points in the direction of travel are pulled to one point at the nose of the photon because they are zero distance apart to the photon, and surfaces near the path are severely bent.

It should also be noted that, once within the lattice of the atoms of glass, the atoms to each side of the photon resume their normal spacing and are no longer foreshortened. This is because they are perpendicular to the direction of travel. Those atoms in front continue to be shortened to meet the photon. Thus the photon length and the glass thickness exactly match, regardless of thickness, if the glass is an exact multiple of a half wavelength.  In that case, the photon completely enters without reflection. If the thickness does not fit the wavelength of the photon exactly, there is a crisis due to a mismatch in which the glass is not quite zero thickness to the photon. The probability of reflection depends on the degree of mismatch, but the reflection decision is made while the photon is still at the front surface and just inside.

There are two effects going on simultaneously: The relativistic effects for the photon and the realistic effects for the observer. The photon fits within the entire experiment (zero thickness, no wiggle time due to no time elapse) while we, as the stationary observers, see the entire experiment where the photon is traveling at c and has to wiggle 130,000 times to get through the glass in a measurable time (about 3 nanoseconds for a foot of glass). One case of quantum weirdness explained by relativistic effects.

Next: Explaining Double Slit Weirdness

Random Thoughts About Relativity

Facts About Relativity  

In order to introduce some of my ideas, it will be good for the reader to become familiar with some of the weird behavior of particles traveling at very high speed, high enough to invoke relativistic effects.

As seen by a stationary observer:

1) The closer a moving object gets to the speed of light, the slower its moving clock gets.

At the speed of light, it is zero – to the moving object, everything is simultaneous.  Start, Splat. The moving object sees the outside world as distorted, getting shorter in length, and at c, the length from here to there is zero, no matter how far the stationary observer measures it.  Photons live in a go-splat world.

2) The closer a moving object gets to the speed of light, the shorter its length gets.

At the speed of light, it has zero length to the stationary observer, but normal length to the moving object.  Everything seems normal to the moving object  until it gets to c – the problem for the moving object at c is that there is no time to seem normal – everything is instantaneous.

3) The closer a moving object gets to the speed of light, the larger its mass gets due to kinetic energy increase (for objects that have mass).

At the speed of light, an object with mass would have infinite mass.   This rules out object with mass ever getting up to c.  Photons do not have mass so they can move at the speed of light.   Nothing with mass can go that fast.

4) The closer a moving object gets to the speed of light, the more energy you have to use to get it there.

You have to give more and more energy to the object to get it  closer and closer to the speed of light. Energy equals mass times speed of light squared.  At the speed of light, the energy required is infinite.  You can never push an object with mass that hard.

What is the equation that describes the way in which time slows down as you approach the speed of light?

The equation is known as the time dilation equation and is:

Δ t = Δ T/ √[ 1 - (v/c)²]    Time dilation

Where  Δ t is the moving object time ticks and Δ T is the stationary object time ticks, v is the velocity and c is the speed of light.

When the velocity approaches c, the term v/c becomes very close to 1 and then the term Δ t becomes very large because the right side is divided by a very small number approaching zero.  This means that the distance between clock ticks gets very long for the moving object.   Time begins to stand still as it reaches the speed of light because the distance between tics becomes infinite.

What happens to space (in direction of motion)?

Δ x = Δ X/√[ 1 - (v/c)²]      Space distortion

Where  Δ x is the ruler mark as measured by the moving object and Δ X is the ruler mark as measured by the stationary object.

When the velocity approaches c, the right hand term approaches infinity.  essentially, a unit measure, such as an inch for the moving object would stretch millions of miles as measured by the stationary object at speeds near c.  

conversely, a foot long ruler moving near c would be invisibly short as seen by the stationary object – a term called foreshortening

Conversely again, the stationary object would seem impossibly close and impossibly short to the moving object near c.  At c, neither could see the other even with the best of instruments until they collide, which would be instantaneous for the moving object.  (To do so would imply that the image was moving faster than c.)

 So someone (very small and massless) sitting on a photon would think they see time normally, but the time of flight would seem to pass instantly from time started to time finished because no time would elapse (Δt very large).   Of course there would be no time to measure time (or even think about it) because the photon would instantly hit the other end of its path, no matter how far away that is.

Someone sitting and watching nearby would see time normally (from their perspective), but in their case, ΔT would be very short (time interval ticks near 0) and they would seem to age quickly compared to the someone riding on a photon.

The total time of flight might seem 100 years to an observer, but seem instantaneous for one traveling at the speed of a photon. The observer would age instantly according to the one moving fast, and the observer would think the one moving quickly didn’t age at all.   Weird isn’t it?  Weird but true.

Similarly, distance gets shorter as an object approaches c as seen by the observer and longer for the observer as seen by the object that is moving fast.

In other words, the time that passes in one time frame (Δ t) is the time that passes in another (Δ T) divided by the square root of 1 minus the velocity squared divided by the speed of light squared.

Enough of this – keep in mind that photons don’t have time to age, and photons arrive the instant they are emitted.  A photon emitted in the furthest star that we can see by telescope arrives the instant it is emitted.   (From the photon’s point of view).   They live an instantaneous “go-splat” life.

From our point of view it may have taken billions of years to get here.  Both viewpoints are valid.  That is the weird nature of relativistic speeds.  Time and space are distorted. 

One last thing:  Effect of speed on atoms:

Atoms are flattened in the direction of their motion.  Normally about 10 -8 cm in diameter they change from a sphere to a flattened disk as they approach the speed of light (from our stationary perspective only).

Particle accelerators have to be designed to account for both time dilation and space contraction in order to work. 

Atoms have mass so they can never reach the speed of light, but particle accelerators push particles, including atoms, to very high speeds that require design changes to keep them on track around their path – changes that involve the equations above.

Next – some of the quantum weirdness explained, example by example from the earlier posts.