It seems that congratulations are in order! At this point in the universe’s 13.76 billion year trajectory, earthlings have reached a comprehensive understanding of all the laws of physics that make up our everyday reality. That’s quite a claim, isn’t it? But the last few centuries of collective scientific research have brought forth the theories and the supportive evidence to make scientists confident that our present knowledge about how the universe works is complete and correct.
At least this is the conclusion of theoretical physicist and natural philosopher, Sean B. Carroll, the author of ‘The Big Picture: On the Origins of Life, Meaning, and the Universe Itself’. Sean is an articulate communicator, and the first part of his book is a clear historical summation of the fundamental theories explaining the forces of the universe. The second part of his book offers the issues before us that are still unresolved.
Remember, scientific theories are not provable in the same way that mathematical proofs are shown to be true. A theory or hypothesis that explains an aspect of the natural world is determined by mathematics and logical deduction. The accumulated evidence either supports or doesn’t support a theory. A theory may become a physical law if it is accepted universally as a cornerstone of science. For example, Einstein’s renowned equation E=mc^2 is a universal law of physics.
Of course, theories can change and evolve as the evidence necessitates. Scientific knowledge is always provisional and subject to revision based on new insights. For example, classical mechanics, first discovered by Sir Isaac Newton in the 17th century, accurately provided the framework for the theories of the forces of gravity, and later electromagnetism. But then two hundred years later, with the publication of Einstein’s general theory of relativity in 1916, a new paradigm broadened our understanding of gravity by showing how mass curves the space-time surrounding it.
Scientific experiments on the subatomic level of physics have provided data that has evolved into the modern comprehensive framework of quantum mechanics. It turns out that the explanation for the deepest level of reality is the concept of quantum fields that give rise to atomic particles along with the forces that hold the nucleus together, and keeps the electron orbiting the nucleus at a steady quantum state. According to quantum field theory, the underlying reality of the universe is the wave function composed of the superposition of quantum fields.
The standard model of particle physics includes all the particles of matter and force-carrying particles – everything except for gravity. The physics of our everyday reality has been superbly described by the comprehensive quantum field theory, dubbed ‘the core theory’ by Nobel Laureate Frank Wilczek and the author of ‘A Beautiful Question’. This rather unwieldy mathematical formula has been correctly validated by all the data produced by scientific experiments performed in laboratories worldwide.
Powerful particle accelerators have been verifying quantum field theory by identifying the particles predicted by the fields but so ephemeral that they are exceedingly difficult to detect. The Large Hadron Collider in Geneva, Switzerland recently confirmed the so-called God particle, the Higgs boson particle. The Super-K Detector in Japan has been verifying and detecting neutrinos and related particles from exploding supernovae. Both facilities are set to be substantially upgraded with even larger facilities to be built. It is money well-spent.
Einstein’s general theory of relativity predicted gravitational waves more than a hundred years age. But since the waves are so subtle, they have not been verified until just recent years. Soon after the LIGO Lab, a giant synchronized detector located in two widespread locations, in the states of Washington and Louisiana came online, the first gravitational waves were detected. They were emitted by an occurrence in the distant past of a powerful binary black hole merger from two colliding star remnants located billions of light-years away. The discovery also revealed the first observation of a black hole.
All these ultra-sensitive detectors have successfully verified the particles and forces that were predicted by theoretical physics. And yet a nagging problem persists – dark matter. How is it that something so necessary to validate Einstein’s general theory of relativity and so fundamental in our understanding of the universe, has yet to be revealed? This is the topic of the new documentary Chasing Einstein showing at the Naro on Wed, Nov 6 with speakers and discussion. The subject matter of the film is rather technical and yet it’s quite accessible for those inquiring minds who want to have a peek behind the curtain.
The story is told by the charismatic scientists themselves. We get to know each of them as they interact with their colleagues and students. Chasing Einstein follows these dedicated individuals as they travel to the giant laboratories built to detect particles and dark matter. They include the world’s largest particle accelerator (CERN) in Switzerland, the largest underground labs (Gran Sasso in Italy), the largest telescope arrays, and the LIGO gravitational wave detector located in both Washington and Louisiana to document the work of these physicist detectives.
The facilities shown in the film are awe-inspiring in their design and complexity, and the whole endeavor instills in me a sense of pride in the noble human quest for pure knowledge, irrespective of the profit motive and of self-interest. I began to appreciate the monumental task of raising the funds, and of the concerted effort to organize a cooperative international team of researchers. The inspiration of their shared mission gives me hope that perhaps, at the 11th hour, the citizens of earth might overcome our selfish fears and destructive bloodlust and redirect our bloated military budgets toward creating a sustainable future.
Physicist and Eminent Scholar at ODU, Sebastian Kuhn, will speak following the showing of Chasing Einstein. He explains “About 84% of all the inferred matter mass in the universe is dark matter – i.e. it cannot be directly observed but deduced from the motion of galaxies. So only 16% of all matter is the stuff we (think we) know and understand – quarks and leptons and their composites.”
He goes on to define the hypothetical force, dark energy, a related cousin. “Dark energy is perhaps even more mysterious than dark matter – while the latter creates more gravity and hence more clumping, the former drives the universe apart at an accelerating pace. If we count all the matter in the universe as energy (because of E= mc^2), it makes up only 32% of the total energy content – hence dark energy must account for the remaining 68%.”
In the next decade, two new telescopes – the Euclid Satellite and the Large Synoptic Survey Telescope – along with the WFIRST infrared telescope, will go online and contribute an immense amount of data towards the search for dark matter and dark energy. Although the astrophysical evidence for both are convincing, they have yet to be produced in particle colliders, nor confirmed by ultra-sensitive detectors, nor directly observed in the cosmos. Physics is now at a crossroads and something must show itself – or not.
One competing theory proposes that dark matter is part of a so-called ‘hidden sector’ – a part of the universe that doesn’t interact with our material universe. But it could still interact via the ‘heavy photon’, a hidden sector version of our regular photon, the quanta that are the force carriers of electromagnetism. Unlike normal matter, dark matter does not interact with the electromagnetic force, meaning it does not absorb, reflect, or emit light – and so it has yet to be detected.
But there is innovative new research underway attempting to find dark matter. The Heavy Photon Search (HPS) project is now up-and-running at our own Jefferson National Accelerator Facility in Newport News. This is a long-running experiment that will generate massive amounts of data to discover a hidden-sector photon, called a dark photon or heavy photon. In the discussion following Chasing Einstein, we will hear about results from the project from Jefferson Lab researcher Sebastian Kuhn as well as project director Stepan Stepanyan.
Ever since my engineering studies pursued at Georgia Tech, I’ve been fascinated with the hidden order of the subatomic world and the scientists who have tried to clarify this reality for the general public. Their research and descriptions of the universe have grown ever larger to go beyond the traditional role of science and have expanded into the realm of natural philosophy. I have been reading several books by brilliant physicists and authors who have tackled the big ontological questions of our day.
In his ‘The Big Picture’, Sean Carroll is fair beyond a fault in presenting the various theories and philosophies that have competed for public attention and dominance. For this reason, I highly recommend his book for the inquisitive and open-minded reader. But one does not have to concur with the conclusions that Carroll hypothesizes, especially his assertion that there are no fundamental properties in the world except those defined by elementary particle physics.
The consensus of most scientific naturalists today is that there is no need for a Creator or for a supernatural presence who intervenes in the natural order of the world. But Carroll takes his naturalism further. He argues that consciousness, values, sensations, purpose, free will, and meaning – are all emergent narratives that Carroll labels collectively as ‘poetic naturalism’, contingent upon the underlying reality of the subatomic laws of physics.
For Carroll, these emergent layers are what compose the complex human realm that we inhabit and the academic disciplines that we employ to investigate and understand the world. He asserts, “Once we start dealing with chemistry, biology, or human thought and behavior, all of the pieces matter, and they matter all at once. We have made correspondingly less progress in obtaining a complete understanding of them than we have, for example, on the Core Theory. The reason why physics class seems so hard is not because physics is hard – it’s because we understand so much of it that there’s a lot to learn, and that’s because it’s fundamentally pretty simple.”
Carroll goes on to make his case for a logical atheism that corroborates the work of other popular atheists like evolutionary scientist Richard Dawkins and philosopher Daniel Dennett. Theirs is a scientific naturalism that views the universe as a giant machine composed of mindless matter. Life and consciousness are an accidental and unintended byproduct of the universe’s physical laws. And although our very existence is problematic for Carroll, he is confident that the gaps in scientific understanding about the origin of life, and the emergence of mind out of the purely physical functions of the brain – will be answered with further scientific study.
In contrast, there are many other philosophers and scientists who subscribe to a more middle ground naturalism, and challenge the reductive physicalism and atheism espoused by Carroll and so many others in the scientific community. Theirs is an ‘open naturalism’ that deems physical law as contributing only part of what makes up our greater reality. Aristotle used the term metaphysics to define that which lies beyond the physical. It’s the very presence and awareness of who we are – the ground of our being. This is the first-person subjective consciousness of our inner experience that lends itself to multiple ontological interpretations. Many philosophers consider this to be a shared causal reality. It’s the embodiment of nonbeing in Buddhism.
Make no mistake, ‘open naturalism’ also rejects the notion that universal physical laws can be interrupted by supernatural intervention. This contrasts with much of orthodox religion along with contemporary new age spirituality. These are belief systems that are founded upon claims of supernaturalism and mythic literalism. Nevertheless, religious belief need not be conflated with such fundamentalism and dogma. There are various religious faiths in both the Western and Eastern traditions that espouse science and naturalism as part of their doctrines.
An expanded scientific naturalism is reflected in a recent book by theoretical physicist and Nobel laureate Frank Wilczek, ‘A Beautiful Question: Finding Nature’s Deep Design’ proposes a universe that embodies beautiful ideas – symmetry, harmony, balance, and economy. This deeper order of beauty is manifest in the elegant forms we observe from the microcosm to the macrocosm of the natural world. And Wilczek thinks it’s no accident that it’s also at the heart of what humans find as aesthetically inspiring.
Physicist and natural philosopher Lee Smolin has critiqued Sean Carroll’s musings and his faith in present-day science as providing the answers for the biggest questions of our day. He finds Carroll’s positivism as misplaced. Smolin asserts “Science is not a fixed set of facts — it is a collection of methods for finding errors in our thinking and hence is structurally self-correcting. We understand a lot, but in the future that understanding will be couched in terms of radically different concepts and principles that illuminate questions that only confuse us now.”
A brief list of these unsolved problems include: a quantum theory of gravity, how the initial state of the universe at the big bang was chosen, how the laws of physics governing our universe were chosen, how did life begin out of nonliving matter, and how is it that the physical brain generates mind and experience? The latter is termed by body-mind dualists as ‘the hard problem of consciousness’.
Smolin attempts to articulate a deeper theory of quantum field theory in his compelling new book, ‘Einstein’s Unfinished Revolution: The Search for What Lies Beyond the Quantum’. As a self-proclaimed ‘simple realist’, he is critical of the ‘anti-realism’ inherent in the current model of quantum mechanics – the quantum view of a very alternative world that does not exist independently of our observations of it. He also argues against what he labels as the ‘magical realism’ popular among theoretical physics today that combines various string theories with concepts of parallel universes to try and explain the quantum world.
Smolin reminds us that Einstein, despite being recognized primarily for his theories of relativity, won the Nobel Prize for his work on quantum theory. And yet Einstein remained unconvinced, and in that sense, a realist. He considered aspects of the theory incoherent and therefore not complete. He spent the last years of his life attempting to go beyond quantum mechanics to include gravity in his theory of general relativity within a grand unifying theory.
Over the years, much of Einstein’s work has now been validated by empirical data. Science has gained access into much of the hidden laws and forces of the universe. The wonder is that the universe is actually intelligible and that creatures like us have attained insight into nature’s secrets. And yes, much of it remains a mystery.
A new paradigm is once again being called for to advance science. It must go hand-in-hand with socioeconomic transformation, and a respect for the natural world and our place as humans in the web of life. If we fail, we’ll soon lose the beauty and diversity of our biosphere, and possibly our civilization. And with it, our discoveries and our ongoing endeavors to comprehend our universe.