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It is not often that we think of events as isolated incidents separated by a vast divide in both physical and virtual distance. In our day to day existence with near instantaneous methods of communication and a pervasively global information network, significant events are easily taken note of. But when the distance separating the event from the recipient exceeds our Earthly bounds, an interesting phenomenon occurs. Even on the scale of the solar system, light from the Sun takes approximately 8 minutes to reach our sunny skies here on Earth. If the Sun happened to go supernova, we would have no acknowledgment of the fact until some 8 minutes after the event actually occurred. While not completely revolutionary, this concept has deeper ramifications if the distances are again increased to a Universal scale.

While we are accustomed to thinking of light as travelling at a fixed speed limit, it is not often that one thinks of gravity as a force that requires time to cross intergalactic distances. But indeed it does. Gravity waves propagate at the speed of light; slight perturbations on the surfaces of incredibly massive objects (eg neutron stars or binary star systems) act as the catalyst for these disturbances. Unimpeded by objects, gravity waves are able to pass through the Universe without effect. They act to warp the nature of spacetime, contracting and expanding distances between objects as the wave passes through that particular locality.

Here on Earth, information is similarly transferred quickly along the Internet and other communication pathways at an average of close to the speed of light. Delays only arise when traffic is heavy (pathways severed, technical problems, increased use). As the distances involved are relatively small in comparison to the speed of the transfer, communication between two points is practically instantaneous. But what if we slow down the speed of travel? Imagine the event occurs in an isolated region of desert. The message can only be transmitted via a physical carrier, thus mimicking the vast distances involved in an interstellar environment. Observer B waiting to receive the message thus has no knowledge of what has happened until that message arrives.

Revisiting the scenario of the Sun exploding, it seems strange that mammoth events in the Universe could occur without our immediate knowledge. It is strangely reminiscent of the Chinese proverb; does a falling tree make a sound if no one is around to listen? Cosmic events are particularly relevant in this respect, as they most certainly do have immense ramifications (‘making a noise’). If the Universe suddenly collapsed at the periphery (unlikely but considered for the purposes of this exercise), our tiny speck of a planet would not know about it until (possibly) many, many millions of years. It is even possible that parts of the distant Universe have already ‘ceased to exist’; the fabric of time and space from the epicentre of this great event expanding like a tidal wave of doom. What does this mean for a concept of Universal time? Surely it must not be dependent upon physical reality, for if it did, surely such a catastrophic event would signal the cessation of time across the entire cosmos. Rather, it would be a gradual process that rushes forth and eliminates regions of both space and time sequentially. The final remaining island of ‘reality’ would thus act as a steadily diminishing safe haven for the remaining inhabitants of the cosmos. Such an event would certainly make an interesting science-fiction story!

Einstein became intimately aware of this universal fact of locality, making it a central tenet in his grand Theory of Relativity. He even offered comments regarding this ‘principle of locality’ (which became a recognised physical law);

“The following idea characterises the relative independence of objects far apart in space (A and B): external influence on A has no direct influence on B; this is known as the Principle of Local Action, which is used consistently only in field theory.”

A horribly simplified description of relativity states that what I experience is not necessarily the same as what you will experience. Depending on how fast you are travelling and in what direction relative to myself (taking into account the speed and direction at which I am travelling), our experience of time and space will differ; quite markedly if we approach the speed of light. Even the flow of time is unaffected, as observers aboard objects travelling at high velocities experience a slowing notion of chronicity compared to their colleagues. It would be intriguing to experience this phenomenon first hand in order to determine if the flow is psychologically detectable. Perhaps it would be experienced as an exaggerated and inverted version of the overly clichéd ‘time flies when you’re having fun’.

Locality in Einstein’s sense is more about the immediate space surrounding objects rather than causes and their effects (although the two are undoubtedly interrelated). Planetary bodies, for instance, are thought to affect their immediate surroundings (locality) by warping the fabric of space. While the metaphor here is mainly for the benefit of visualisation rather than describing actual physical processes, orbiting bodies are described as locked into a perpetual spin, similar to the way in which a ball bearing revolves around a funnel. Reimagining Einstein’s notion of relativity and locality as causality (and the transmission of information between two points), the speed of light and gravity form the main policing forces in managing events in the Universe. Information can only travel some 300,000 km/s between points, and the presence of gravity can modify how that information is received (large masses can warp transmissions as in gravitational lensing and also influence how physical structures interact).

Quantum theory adds to the fray by further complicating matters of locality. Quantum entanglement, a phenomenon whereby an effect at Point A instantaneously influences Point B, seems to circumnavigate the principle of locality. Two points in space dance to the same tune, irrespective of the distances involved. Another quantum phenomenon that exists independently of local space is collapsing wave functions. While it is currently impossible to affirm whether this ‘wave’ actually exists and also what it means for the nature of reality (eg many worlds vs Copenhagen interpretation), if it is taken as a part of our reality then the act of collapse is surely a non-local phenomenon. There is no detectable delay in producing observable action. A kicked football does not pause while the wave function calculates probabilities and decides upon an appropriate trajectory. Likewise, individual photons seem just ‘know’ where to go; instantly forming the familiar refraction pattern behind a double-slit grating. The Universe at large simply arranges its particles in anticipation of these future events instantaneously, temptingly inviting notions of omniscience on its behalf.

Fortunately, our old-fashioned notions of cause and effect are preserved by quantum uncertainties. To commit the atrocious act of personifying the inanimate, it is as though Nature, through the laws of physics, protects our fragile Universe and our conceptions of it by limiting the amount of useful information we can extract from such a system. The Uncertainty Principle acts as the ubiquitous protectorate of information transfer, preventing instantaneous transfer between two points in space. This ‘safety barrier’ prevents us from extracting useful observations regarding entangled particles without the presence of a traditional message system (need to send the extracted measurements taken at Point A to Point B at light speed in order to make sense of the entangled particle). When we observe particles at a quantum level (spin, charge etc) this disturbs the quantum system irrevocably. Therefore the mere act of observing prevents us from using this system as a means of instantaneous communication.

Causality is still a feature of the Universe that needs in-depth explanation. At a higher level is the tireless battle between determinism and uncertainty (free-will). If every event is predetermined based on the collisions of atoms at the instant of the Big Bang, causality (and locality) is a moot point. Good news for reductionists whom hope to uncover a fundamental ‘theory of everything’ with equations to predict any outcome. If, on the other hand, the future really is uncertain, we certainly have a long way to go before an adequate explanation of how causality operates is proposed. Whichever camp one claims allegiance, local events are still isolated events whose effects travel at a fixed speed. One wonders what the more frustrating result of this is; not having knowledge about an important albeit distant event or realising that whatever happens is inevitable. The Universe may already have ended; but should we really care?

Quantum physics is a fascinating branch of modern science that has grown in popularity. Terms such as “the uncertainty principle”, “quantum entanglement” and “probability waves” have all become commonly-used phrases in the scientific community. In the same way that Newtonian mechanics explains the world of the very big, (the orbits of planets, falling apples) quantum physics aims to improve our understanding of the very small (sub-atomic scales). Once objects start interacting at a smaller level, quantum mechanics takes over and produces some weird and wacky results. What Newton’s laws and (to an extent) Einstein’s special and general theories of relativity have in common sense and comprehensibility, quantum physics makes up for in its plain weirdness.

In the wacky world of the quanta, particles appear out of nothing and vanish again in an instant. Particles separated by infinite distances show characteristics of ‘entanglement’; that is, measurements taken on one particle instantaneously affect the state of the partner (seemingly violating the faster-than-light limitations of general relativity). Similarly, quantum particles exhibit tunneling behaviours. Being probabilistic in nature, the quantum wave equation for any given particle will expand as a function of time. Occasionally, this wave (or probability of existing in a particular position) will penetrate insurmountable obstacles (that is, distances or barriers where the energy to escape them is more than the particle’s kinetic energy). In effect, the particle has ‘tunnelled’ through thin air.

The probabilistic nature of quantum physics introduces some worrying implications for the nature of reality. In particular, the Copenhagen Interpretation (one leading view on what the quantum calculations translate into in the macroscopic world) posits that an observer is needed to collapse the wave functions, creating what we see as real. Taken literally, this means that nothing exists if we aren’t watching. The falling tree in a deserted forest really does make no sound, solving the Chinese proverb succinctly. Erwin Schrodinger, one of the pioneers of quantum theory and the man behind wave equations, disagreed with this interpretation most vehemently. Schrondinger’s cat was the fruits of his protest; a thought experiment introducing the paradox that this interpretation brings.

Schrodinger’s thought experiment goes a little something like this. It states that a cat, sealed off totally from the outside world and attached to a death device will exist in a superposition of quantum states. Its probabilty wave will spread out over time, with the cat existing as both dead and alive at the same time. The hypothetical death device consists of a decaying radioactive source, emitting particles that are detected via a Geiger counter. The probabilty wave spreads in such a manner due to the underlying quantum randomness that controls the process of radioactive decay (tunnelling allows beta particles to escape the overwhelming pull of the weak nuclear force). Thus, once a sufficient period of time has passed and the probability of the radioactive substance emitting a particle (or not) is exactly 1/2, the cat is said to be both alive and dead.

Schrodinger was not advocating the truth of this experiment, rather using it instead to draw attention to the paradox and ‘can of worms’ that the Copenhagen Interpretation had brought about. While the experiment may indeed be possible in the realm of quantum uncertainty, it certainly requires a definite leap of faith away from the common sense interpretation of everyday occurances. The major premises that this argument requires us to accept is that a) probability waves exist (that is, quantum particles exist in a superposition of possible states), b) an observer is necessary to collapse the function and bring about reality and c) the observer must be intelligent (namely that there is something inherently unique about conscious beings and their quantum-collapsing ability).

Firstly I will take a minor detour and actually lend a snippet of support to the thought experiment. The old saying ‘a watched pot never boils’ seems to make no practical sense, however a simple rephrasing to ‘a watched quantum pot never boils’ is closer to the truth. Researchers imitated the physical process of boiling on a quantum scale by bombarding a collection of beryllium atoms with microwaves. These incoming microwaves were then absorbed by the atoms, booting them up from a low to high energy level. The researchers knew that the time period for all atoms to become excited was around 250ms, therefore by beaming a burst of laser light into their atomic midst, the number of atoms still in their lower ground state could be counted (excited atoms cannot absorb the incoming photons, therefore only the atoms in the lower, less excited state will be affected). Initially they only looked at 125ms, when around half the atoms should be excited. And they were! Then then increased the number of observations, looking four times in 250ms. They found something unexpected. With each successive observation, the atoms would ‘reset’ their energy levels; in effect, by increasing the number of observations the atoms would never reach the higher state. The watched pot never boiled! (For further reading, search for “The Quantum Zeno Effect“).

The explanation here directly supports one of Schrodinger’s main requirements for the thought experiment. Quantum probability waves exist. What the researchers believe happens is that the probability wave of each atom is artificially collapsed by the act of observing. When the atoms are free from observation, the probability wave is free to spread out, increasingly the likelihood of observing all the atoms similarly excited. By looking multiple times, the wave is collapsed prematurely, preventing the wave from spreading out to its potential equilibrium state. In effect, the intent of the observer controls to outcome. If you want half the atoms to become excited, no problem, look at time t/2. You want the pot to never boil? OK, just keep watching continuously.

However, Shrodinger’s second and third requirements denoting the features of the observer doing the collapsing are not so easy to support. Why are humans so arrogant to believe that there is something inherently special about us that we are required for the universe to exist? It simply makes no sense whatsoever that outside of our measly existence, nothing is actually real until we look. Rather, the quantum constituents may be probabilistic however the virtual seething mass of particles that zip around and interact with each other must surely provide the means to collapse wave functions. A conscious observer is not needed for reality to have any objective meaning (what about prior to the evolution of conscious beings – are we all being observed by an omnipotent being which makes us all real?) The universe itself must surely be doing the observing and the collapsing, through the myriad of interacting particles.

I believe the main problems people suffer from when discussing quantum mechanics is that they try to relate it to pre-existing notions of reality. They also place the importance of human consciousness above the fact that the universe will continue to exist regardless of whether we are around to watch. This deluded geocentricism has long plagued humanity, causing major scientific retardation throughout the ages (Aristotle et al). The implications of quantum mechanics on reality still holds many mysteries. If watching a quantum pot causes it to freeze in its initial state, what does this mean for reality and intent (and also free-will)? If quantum processes control the operation of minds, perhaps it will also prove to be the mysterious bridge that spans between Cartesian mind/body duality. Perhaps the secret to consciousness is the uncertainty introduced by the quantum reality that underlies every physical process.

Stopping for lunch at the usual time I made my way to my seat in the corner of the canteen beside the rack of journal articles. One thing I love about working for a CRO is the plethora of sciency-related readings available in the staff library. The August issue of New Scientist caught my eye with its intriguing title; “Spooks in space“. Now before we get started I would like to make one thing clear; I am not a physics guru, mathematical representations of physical theorems not only confuse me but I also question the usefulness of over complicating a subject that already holds such a stereotype of requiring intellectualism and genius in order to fully appreciate it. Therefore, while the first section will outline a (very) basic foundation of the theories, I hope that the second part is more thought provoking and practical for discussion.

Boltzmann brains, named after the 19th century thermodynamicist Ludwig Boltzmann, are a hypothesised phenomenon arising from the cosmological interpretation of the second law of thermodynamics (the complexity of the universe will always increase). Boltzmann’s original idea was that random thermal fluctuations may have been responsible for the creation of our universe. Delving deeper, Boltzmann proposed that our observable universe (with its low level of entropy and thus higher organisation) may be a figment of our own imagination; we may simply be the result of a ‘random fluctuation’ within another universe of higher entropy (lower organisation, higher chaos).

The Boltzmann paradox is thus; if we are the result of a a random fluctuation, our likelihood of existing is much less probable than a universe full of Boltzmann brains. In short, the billions of self-aware brains that make up humanity (remember, if we are due to random fluctuations) are less likely than a single, self-aware and conscious entity with false memories and perceptions of the world around it.

The good news is, we aren’t Boltzmann brains! I believe the argument here is that in order for Boltzmann brains to arise, the target universe from which they are formed must be at a high level of entropy. Due to the fact that we exist in a universe with low entropy (being relatively young) tends to rule out the likelihood of so many brains spontaneously arising all with false memories and perceptions of the universe. The Boltzmann scenario is only salvageable if our portion of the observable universe is a small ‘bubble’ within one much larger that has high entropy (chaotic and prone to random fluctuation).

Boltzmann brains have vast theological implications, if correct. They may form the basis for a rationalised and scientific explanation for the existence of a god. As a devout atheist (who has gained some tolerance for religious discussion over the years) I do hold an active interest in rational theological discussion. The Boltzmann hypothesis seems to be the first plausible (although still highly unlikely) explanation for the existence of god that doesn’t involve mindless devotion and ‘leaps of faith’. Below is a post I found that outlines a basic theory, which I hope to develop further.

“Getting back to Boltzman Brains, it occurred to me that a Boltzman Brain could provide a naturalistic explanation for the existence of God.
The first cause proof of God is that there has to be a first cause to our universe. Atheists, however, always retort: “Oh yeah, then what caused God?”
So, a theist can now say that God was a spontaneously-formed Boltzman Brain formed from the formless chaos of Nothingness.
This response also rescues God from the charge that if He exists, then He is Nothingness itself; God would really be a Something rather than a Nothing if He were a Boltzman Brain.
Since there is no existence more lonely than being a disembodied, utterly alone, Boltzman Brain, God created the world and us in order to have some company. . ” – Warren Plats, link.

Thus the requirements for a Boltzmann-based god would be;

  1. A sufficiently old universe (infinite age?) to allow for the spontaneous formation of a being with self-awareness and omniscient capabilities.
  2. Methods for that being to interact with its universe or itself in order to create the target universe.
  3. A desire on the god’s behalf to create the target universe.
  4. Allowance of the god’s existence for a sufficiently long enough period to both formulate and enact the creation (random fluctuations in chaos can more easily remove order than create it – a cup is more likely to drop and smash than it is to jump up and reform).

Moving on from these requirements, a possible Boltzmann god may then arise from the constituents of an infinitely old universe rearranging themselves spontaneously so as to create order from chaos and in the process, give rise to an all knowing, all powerful entity. As a side note I would like to make the point that the name “Boltzmann Brains” is slightly misleading; our ideas of what constitutes consciousness is often clouded by our own experiences. So far, humanity is the only fully conscious entity in our observable universe, therefore we tend to describe consciousness in terms of ourselves. Boltzmann brains, and in fact other more exotic forms of alien consciousness need not necessarily be made up of the same stuff that makes up our brains. Nerve cells, blood vessels and electrical impulses can give way to, and are less likely to produce consciousness than more simple models such as silicon chips and even clouds of interacting atoms (such as Hydrogen, the most abundant element in the universe). Given enough time, anything that can happen, will. In this case, a universe that has existed for an infinitely long period has a higher likelihood of producing such a conscious entity.

But the question remains of how such an entity can spark the creation of a universe that is suitable to lifeforms like us. Was it external manipulation such as a conscious and purposely directed fluctuation that gave rise to our universe? Or was it an internal rearrangement of its own constituents (eg; the creation of a singularity); a self-directed suicide on behalf of the entity that created our reality? The latter opens up the possibility of a cyclic universe, in that everything that has come to pass will happen again. The eventual creation of a god-like Boltzmann brain serves as the eventual catalyst which prevents the perpetual darkness that an infinitely expanding universe would bring and starts everything afresh.

I hope to revist the topic of Boltzmann brains sometime in the future. What seemed as a relatively ‘goofy’ and niche area of philosophical physics quickly spills out into a question of reality itself, the implications of Boltzmann brains as typical observers (can we really be sure that our measurements of the universe are ‘really real’) and the usefulness of Boltzmann brains as a theological model for creationism (albeit in a distinctly more science-heavy form).