Since I am an atomic physicist, this week I break with tradition of talking of the mysteries of life and the universality of cell signaling, and make the point that everything in the universe is signaling, even at the atomic level. Atoms pass energy and electrons back and forth in forms of waves traveling through space. We might wonder what space really is and what defines it. This gives us something to think about, how can we measure space?
Many people in history have attempted to find an absolute standard by which everything else can be measured. A standard for measuring distances or lengths is a great example. The length of the king’s foot (his supernal majesty) was thought to be an absolute divine standard. Unfortunately, kings turned out to have inconsistent feet and were mortal and died. Looking for a somewhat better standard, it was agreed that a meter would be determined as one ten-millionth of the distance between the north pole and the equator, along the octant line passing through Paris (of course). This distance also varied with sun and moon cycles and was somewhat difficult to measure perfectly. The standard for measuring time was a bit easier, a solar day could be divided into equal segments of time. This could be tied to the movement of a pendulum or some other mechanical or electrical device that beats out units of time. With the infinite wisdom of men, an hour was chosen as (1/24 of a day) broken into 3600 (60 x 60 seconds). This turned out well, most everyone on earth uses a second to measure time and has the same clock. With advanced electronics, clocks that measure at the order of 1 billionth of a second (a nanosecond) are becoming more important.
Could there be an absolute standard of measurement that is determined by some unchangeable property of the universe by which we can measure distance and time? The answer comes from the study of light in physics. The speed of light in a vacuum is thought to be absolute everywhere denoted as the constant “C”. The speed of light is measured at about C = 300,000,000 meters per second. The speed of a ray of light is the same whether measured by someone standing on earth or measured by someone on a satellite traveling at a relative speed of 3,000 meters per second through space. The speed of light is measured as constant regardless of the speed of the source or the reference frame of the person taking the measurement.
What exactly is light? We understand light to be made of electromagnetic waves passing through space. The properties of light are thought to be the same everywhere in the universe. Possibly, then it makes sense to measure time and distance based on the nature of how electromagnetic waves travel through space. We have made atomic clocks, that measure time based on the number of times a cesium atom at resonant frequency vibrates back and forth in a metal tube. One second is measured at 9,192,631,770 such vibrations of a cesium atom. We can measure time by counting how many electromagnetic waves of a constant frequency pass through a wave detector, the frequency of the wave is determined by the properties of a specific atom, which beats out the same frequency anywhere we measure it in the universe as far as we know. By studying light, can we find an absolute standard for measuring time and distance?
The idea of measuring time by counting waves is interesting. Suppose we found a beach where exactly 100 waves would hit the shore every hour. Suppose the frequency and speed of the waves were constant. We then would have a standard clock, one hour is the time it takes for 100 waves to hit the shore, and our standard of distance could also be the distance between wave crests approaching the shore. This makes a good case for using electromagnetic waves to determine an absolute standard to measure time and space, determined only by the properties of light in the universe.
If we base measurement standards on electromagnetic waves, some very beneficial and enlightening ideas are revealed. First off, we do not need to redefine the unit of time we use, the unit of a “second” is already adopted as the unit of time everywhere on earth. With an atomic clock, we have determined that a certain given number of waves that hit a detector defines exactly one second. Now for a distance standard we can utilize the constant speed of light to define a unit of distance as how far light travels in a specified amount of time. A convenient standard, for example, would be the distance light travels in one billionth of a second, a nanosecond (ns): 1 ns = 30 cm (close to a foot). We then can measure everyday distances in units of nanoseconds (ns). Recently the meter has been redefined by the light standard so that light travels in 1 sec = exactly 300,000,000 meters. Incidentally, we also use the light-year to measure astronomical distances. I do not expect that everyone on earth start measuring distance in units of “ns” anytime soon; we already have enough confusion between Metric and US units. There are too many machines and buildings in the world to retool all of them.
I do suggest, though, that we think of the implications. If distance is measured as this unit of time, then the speed of any object would be measured in units of nanoseconds per second. This makes the measurement for speed a “unitless” percentage relative to the speed of light. A speed of one “nano” (billionth of the speed of light), for example, gives us: 1 nano = 1.08 Km/hr. Thus 100 nanos would be 108 Km/hr or about 65 mi/hr. A nano would be a natural unit for vehicle speeds. This would also set the universal speed of light as “C = 1”, with no associated units. It would be interesting to consider the implications of how we measure mass and energy. If C = 1, then Einstein’s famous equation E = MC^2 would be rewritten as E = M, or energy = mass. The equivalence between energy and mass could allow us to come up with an absolute measurement standard for the mass of an object based on some assigned unit of energy. This is interesting, as we tap into the nature of space, not only is there an equivalence between time and distance, but also between mass and energy. Can you see where this is leading us?
Our attention now turns to finding a natural unit for energy. We go back to the beach where exactly 100 waves are hitting the shore every hour. Each wave has a certain amount of energy. If we now double the frequency of the waves, let’s say that 200 waves every hour are now hitting the shore, we have also doubled the amount of energy we have hitting the shore. There is a directly proportional relationship between the frequency of the waves and the amount of energy delivered. This is reflected in Planck’s famous relationship E = h * f, where “h” is a universal constant (Planck’s constant) that relates the frequency of the electromagnetic wave (f) to the amount of energy (E) that is contained in a packet of waves (a photon) at that frequency. Planck’s constant has been proven to also be a universal characteristic of nature. In metric units “h = 6.62607004 * 10^-34 Joule Seconds”. If you are not familiar with scientific notation, this means that Planck’s constant is 0.000000000000000000000000000000000662607004 Joule Seconds. A Joule is the amount of energy you get when you drop a 1 Kg mass the distance of 1 meter (at sea level). Planck’s constant is a very small number, and so it takes an enormous number of electromagnetic waves to be equivalent to a measurable amount of energy. For example, if 1,000,000,000,000,000,000,000,000 (1 Yotta=24 zeros) waves are in 1 ns (a distance of 30 cm) it would contain only 0.662607004 Joules of energy (the energy of a pound weight dropped from your hand to the floor). It might be worth mentioning that there are an immense number of photons (wave packets) in our environment, so a Yotta of waves would contain the sum-total energy/frequency of waves from many photons. These huge numbers are not so unreasonable on the atomic scale, a Yotta of water molecules would fit into a thimble, for example.
If we look at very high frequencies (measured in Yotta’s) then, we can come up with a natural unit for energy: 1Y/ns = 0.662607004 Joules. Or in units of energy used in heating your house: 1000 Y/ns = 662.6 Joules (or 0.628030262 BTU’s). Once again, I am not campaigning to make Y/ns to be a universal unit for energy, but some interesting concepts emerge. When we measure energy in terms of frequency, the units for energy turn out to be 1/sec, that is a unit of 1/time.
Looking back, we have measured distance with units of time (seconds) and now we are measuring energy with units of 1/sec. All these measurements are in units of time and inverse time. We see now that in these natural units, we have exploited the known universal properties of space to reduce the units of distance and energy with that of just two types of units, time and inverse time respectively. Can we read something more into this?
Before we finish, let’s see if we can find a good natural unit for measuring the mass of an object. As we discussed, Einstein’s famous equation in our natural units is E = M. If we want to adjust this to our units, we realize from Einstein’s equation that it takes quite a bit of energy to amount to any measurable mass. The prefix “Peta” (P) amounts to 1,000,000,000,000,000 (15 zeros). One Peta Y/ns (PY/ns) = 7.3623… grams (about 0.26 oz). This is the final unit of measurement we will define at this time. We have shown that even mass can be expressed in units of 1/time. One interesting observation is that defining new these new units of measurement does not change any of the laws of physics, all of the old formulas can be rewritten to reflect the new units, though they may not immediately look familiar to us (E = MC^2 ->PE = M or 10^15 E = M), but they might provide some new insights and computationally be easier, since all the natural constants, like h and C, have much easier-to-remember numbers. (C = 1, h = n/Y = 10^-33). Theoretical physicists already have their favorite system of natural units to make computations easier that I will not mention here.
It is interesting to think about what all this might mean about the nature of nature. Physicists use the name “space-time” to describe the physical place where we exist. We now see that there is not much of a difference between space and time, as both can be described with the same unit of measurement. This concept becomes helpful when Einstein’s theories of relativity are contemplated. The idea that the speed of light is constant in all frames of reference has significant implications. Relative time and distance can be interchanged depending on the relative velocity, there is no absolute reference for either. If you were a tiny point and were to travel at very near the speed of light, the light coming from behind you would take forever to reach you, thus time would have to almost stand still in your frame relative to the source of the light. For all photons, time stands still in their own frame. It all works out but requires much thought. The idea that matter and energy can be described as waves of various frequencies leads us to the thought that possibly all matter is simply made from very densely packed waves of vibrating pieces of space-time. This leads to a better understanding of Quantum Theory, wave functions, particle-wave duality, matter-antimatter annihilation, mass-energy exchange in atoms, existence of quarks and so on. These concepts ultimately bring us closer to the sought-after theory of everything.
If everything is made out of waves in space-time that carry information from one place to another, then everything is signaling. Think about it.