From: mk_thisisit
At the National Laboratory of Atomic and Molecular Physics in Toruń, groundbreaking tests of quantum physics are underway, with significant resources dedicated to understanding if physics, as we know it, remains constant throughout the observed universe [00:00:00]. This research seeks to push the boundaries of current knowledge by several significant digits, mastering technologies to the limits of what is physically possible [00:00:41].
The Standard Model and Fundamental Constants
The Standard Model of particle physics is based on quantum field theory, which describes particles not as existing balls but as excitations of quantum fields [00:02:04]. An electron, for example, is an excitation of a quantum field [00:02:18]. Rather than requiring high energy to test quantum theory, researchers are approaching the Standard Model from a different perspective, using relatively low energies but achieving extremely high measurement accuracy [00:02:36]. This method allows for insights into the Standard Model without needing very high energy inputs [00:03:02].
A crucial aspect of the Standard Model is that it contains approximately 20 parameters (fundamental constants) that must be determined experimentally [00:03:28]. These constants are dimensionless, meaning they do not depend on the system of units chosen for measurements; they primarily represent ratios of elementary particle masses and interaction strengths [00:03:44].
Are Fundamental Constants Really Constant?
A key scientific question is whether these fundamental constants are truly constant, or if they can change over time or vary across space [00:04:07]. Humanity invests enormous resources to determine if physics, particularly in terms of fundamental constants, is the same at the edges of the observed universe [00:04:16].
Speed of Light is Not a Fundamental Constant
The speed of light is not considered a fundamental constant in the same way as dimensionless constants [00:05:08]. It is a fixed parameter in the SI unit system, used to define the measure of length based on the extremely precise atomic clocks that define time [00:05:45].
Any change, even minimal, in these constants could drastically alter the structure of proteins or other fundamental processes, meaning life as we know it can only function within a strictly defined set of these constants [00:04:40]. Observing any variation in fundamental constants, such as the fine structure constant (which indicates the strength of electromagnetic interaction), would be a discovery worthy of a Nobel Prize [00:13:14].
The Toruń team, using optical atomic clocks, has already shown that the fine structure constant, if it oscillates in time, does so less than at a significant point, having moved previous knowledge by several significant figures [00:14:09]. As of today, no changes in fundamental constants have been measured [00:13:07].
The Anthropic Principle and a More General Model
The observation that constants appear “perfectly matched” for life to exist is an intriguing one [00:07:11]. However, a potentially trivial solution to this “anthropic” or “anthropocentric” view could be a more general model beyond the Standard Model that predicts the values of these constants, thus resolving the mystery [00:08:38].
Testing Quantum Theory at the Molecular Level: Trapping Molecular Hydrogen
The current project aims to trap molecular hydrogen, something no one has managed to do on Earth so far [00:13:30]. This is because molecular hydrogen is the smallest, simplest molecule in nature [00:16:13]. It interacts extremely weakly with electric and magnetic fields, rendering conventional laser cooling and trapping techniques ineffective [00:16:32].
The team is developing cutting-edge experimental technologies that push the physical border [00:17:09]. They plan to use an ultra-strong laser field, generated in an optical cavity with ultra-high finesse [00:18:24]. This cavity will trap photons, allowing their average power to reach megawatt levels [00:18:40]. This allows for precise interaction with weakly interacting molecules [00:17:30].
Why Molecular Hydrogen?
Molecular hydrogen is chosen because it is the simplest molecule, consisting of just two protons bound by a cloud of two electrons [00:19:55]. This simplicity makes it a “countable system” that can be calculated extremely precisely from basic theory [00:20:03]. The goal is to extend testing of quantum theory beyond atomic physics to molecular physics, similar to how the hydrogen atom was crucial in the development of quantum theory [00:19:47].
The experiment involves generating almost 1 MW of continuous optical power trapped between two mirrors within a cryogenic vacuum chamber [00:20:24]. Special cryogenic modules isolate the system from temperature and blackbody radiation, lowering the temperature to 4 Kelvin [00:20:46]. Laser forces will be so significant that the molecules will levitate, preventing them from escaping due to thermal or gravitational forces [00:21:33].
From Quantum to Classical: The Problem of Decoherence
One of the most interesting issues in modern physics is how the transition occurs from the non-intuitive, probabilistic quantum world to the deterministic classical world [00:09:39]. In quantum mechanics, an object can exist in a superposition of states, meaning it can be in multiple places simultaneously [00:12:14]. When a measurement is made, this superposition collapses, and a single classical outcome is observed [00:10:40].
Professor Żurek’s theory of decoherence addresses this [00:09:54]. From the quantum perspective, probabilistic descriptions and superpositions are natural, but the classical world appears strange [00:10:04]. Decoherence explains how the interaction with the environment causes a quantum system to lose its coherence and appear classical [00:12:03].
The Observer Effect
In physics, the “observer effect” refers to how the act of measurement itself can disturb a quantum system. However, as currently understood, human consciousness plays no role in this effect [00:27:08]. Whether a conscious observer or an automaton makes the measurement, the transition from quantum to classical is the same; what matters is that photons or other particles interact with the system, potentially altering the result [00:27:32].
The Quantum Vacuum
Even perfectly evacuated space is not truly empty [00:24:41]. It is permeated by quantum fields that oscillate, creating and disappearing “virtual particles” [00:24:48]. The hydrogen molecule, as a specific effect of the full Standard Model, “feels” these zero-point oscillations of the vacuum [00:25:02]. Ultra-accurate measurements allow scientists to test the Standard Model by observing these subtle interactions [00:25:17].
Future Directions in Physics
Atomic physics, particularly “Tabletop experiments” that fit into a few dozen square meters of lab space, offers a way to invest in huge measurement accuracy rather than huge energy [00:32:07].
Showing the Limits of the Standard Model
One exciting goal is to find the limits of the Standard Model, to “catch” it in a corner where it doesn’t work properly [00:32:30]. This includes investigating if the electron has an electric dipole moment, which would indicate a slight non-spherical distribution of charges, a finding that would require a redefinition of the particle within the Standard Model [00:32:50]. This would be a significant contribution to discrepancies between theory and experiment in cosmology if it was found.
There’s an ongoing debate about building even larger colliders, which are gigantic investments (hundreds of billions of euros) [00:34:45]. The question is whether such immense funds are the best targeted way to spend money given pressing global social issues like global warming and migration [00:33:52].
The Nature of Reality and Consciousness
Humanity’s cognitive abilities, including abstract thinking, allow us to explore the world [00:29:26]. However, it’s a question whether all problems are cognitively accessible to us, especially given our three-dimensional perception and sense of time [00:28:47].
A profound question in physics is how consciousness arises from the Standard Model [00:42:37]. It’s astonishing that a mechanistic understanding of nature at the fundamental level gives rise to a subjective observer who can realize they exist [00:42:54]. While we understand how classical and even quantum computers work, we have “absolutely no idea” how consciousness is transformed from logical actions of neural networks [00:43:30].
Some, like Professor Roger Penrose, speculate about quantum effects within the brain, such as microtubules, as potential mechanisms for consciousness [00:43:42]. However, this is still a mechanistic description, simply using quantum language instead of classical [00:43:52]. While consciousness is the most frequently observed experimental fact (our own subjective experience), it remains difficult to pose scientifically testable questions about it [00:44:16].
The Standard Model provides a necessary condition for consciousness, but it’s unknown if it’s sufficient [00:45:12]. There might be another “piece of physics” or “piece of reality” not yet understood, or consciousness may simply emerge from the known Standard Model [00:45:19].
Origin of Matter
Hydrogen constitutes 78% to 99% of all matter in the universe [00:29:53]. This is because at the beginning of the Big Bang, the simplest bonded systems – protons and electrons – were naturally created first [00:30:22]. Heavier nuclei formed later through nuclear reactions, for example, helium in the very early universe and most heavier elements inside stars [00:30:33].
While a large part of elementary particles were created in the Big Bang, as excitations of quantum fields, particles can also appear and disappear [00:31:02]. Therefore, it’s not certain that every elementary particle in our bodies was necessarily created during the Big Bang, though it is certainly possible that some were and migrated to us [00:31:21].
The Beauty of Physics
Physics offers a unique “elite beauty” in the mathematical structures that describe reality [00:38:09]. The realization that nature can exhibit mathematical patterns like Pascal’s triangle without being explicitly asked for is a profound insight into the universe’s inherent order [00:38:47].
The Core Principle of Science
“Describe reality so that the description is consistent with reality” [00:40:09]. This seemingly trivial conclusion, reached around the time of Newton and Galileo, is considered the greatest breakthrough in the history of science [00:40:22]. It emphasizes the importance of confrontable, falsifiable questions, in contrast to poorly posed questions (like “what is mathematics?”) which cannot be validated against reality [00:41:01].