The Four Distinct Interpretations of 'Nothing' in Science

Everything around us, including ourselves, had a beginning. But where did it originate? Today’s Universe is replete with “matter.” At the most basic level, everything we perceive, feel, and engage with comprises subatomic particles, which have formed larger constructs—humans, planets, stars, galaxies, and galaxy clusters—over the Universe’s timeline. All these entities adhere to the same physical laws and exist within the shared spacetime we occupy.

The elements we experience in the Universe today have only existed for a finite duration. At some point, the Universe did not host galaxies, stars, or atoms, implying they must have emerged from a certain origin. An intuitive response might suggest that they came from “something,” but that is not always the case; they could have originated from nothing. What does “nothing” signify in a scientific context? Depending on who you consult, you could receive one of four distinct explanations. Here’s a breakdown of each.

The Universe is a remarkable and diverse environment, filled with various forms of matter and energy, unfolding within spacetime as dictated by the laws of physics. For instance, consider the Hubble space telescope's capture of galaxy cluster IDCS J1426.5+3508. However, how much must be removed before we are genuinely left with nothing? (NASA, ESA, AND M. BRODWIN (UNIVERSITY OF MISSOURI))

1. Absence of Fundamental Constituents

To create “something,” the essential building blocks must exist. You cannot have galaxies, stars, planets, or even humans without the requisite particles. Everything we know is constructed from subatomic particles—the foundational elements of our Universe.

When beginning with a matter-rich Universe, we can comprehend its expansion, cooling, and gravitational effects leading to the current state of the cosmos. We understand stellar life cycles and how they generate heavy elements necessary for forming low-mass stars, rocky planets, and organic compounds, eventually paving the way for life. However, how did we arrive at a Universe filled with matter rather than one balanced with matter and antimatter? This encapsulates the first scientific interpretation of deriving something from nothing.

Following the annihilation of quark and antiquark pairs, the remaining matter particles fuse into protons and neutrons, surrounded by neutrinos, antineutrinos, photons, and electron/positron pairs. A surplus of electrons will correspond to the number of protons, maintaining electrical neutrality. The origin of this matter-antimatter imbalance remains one of the most significant conundrums in modern physics. (E. SIEGEL / BEYOND THE GALAXY)

One of physics' greatest puzzles is this: if the laws dictate that matter and antimatter are produced in equal quantities, how do we end up in a Universe solely composed of matter? Every celestial body observed is made of matter, not antimatter. How did we achieve an excess of these vital raw materials if the Universe did not initially possess them? This explains the notion that matter in our Universe emerged from nothing. The origin of this imbalance, known as baryogenesis, poses a formidable challenge for physicists today, with numerous theories proposed, yet no definitive answers.

The Universe is a fascinating entity, and its current state is a marvel. Although our most breathtaking images of space are filled with galaxies, a significant portion of the Universe is entirely devoid of matter, galaxies, and light. We can only ponder a Universe that is genuinely empty. (NASA, ESA, HUBBLE HERITAGE TEAM (STSCI / AURA); J. BLAKESLEE)

2. Nothingness as Empty Space

Some may define nothingness as an absolute void—an absence of all things. If you adopt this perspective, the first definition appears insufficient as it still implies the presence of “something.” To achieve true nothingness, every fundamental component of matter must be eradicated. This includes all particles and antiparticles, from elusive neutrinos to dark matter.

If it were possible to eliminate every single particle, what remains would be merely empty space. If no matter, radiation, or identifiable quantum exists, you would be left solely with the void of empty space. For some, this definition embodies the scientific essence of “nothingness.”

Yet, even under this extreme scenario, certain physical principles persist. The laws of physics remain intact, implying that quantum fields still pervade the Universe, including the electromagnetic and gravitational fields, as well as the Higgs field and nuclear force fields. Spacetime continues to exist according to General Relativity, with the fundamental constants retaining their observed values.

Moreover, the zero-point energy of space persists, existing at a positive value. Today, this manifests as dark energy; prior to the Big Bang, it fueled cosmic inflation, which ultimately led to the formation of the Universe. This concept is where the expression “a Universe from nothing” originates. Even in the absence of matter or radiation, this interpretation of “nothing” can give rise to a remarkable Universe.

3. Nothingness as the Lowest-Energy State

Currently, our Universe possesses a zero-point energy that is positive and non-zero. It remains uncertain whether this represents the true lowest-energy state or if a more minimal state exists. It’s conceivable that we inhabit a false vacuum state, with the actual vacuum potentially being closer to zero or even negative.

Transitioning to this ultimate state could lead to catastrophic changes in the Universe, a scenario referred to as vacuum decay. Such an event would have dire consequences for existence; for example, photons would become massive particles, and the electromagnetic force would only operate over short distances, drastically reducing solar energy reaching Earth.

In contemplating this state of true nothingness, we envision an ideal scenario that still upholds the laws of physics—albeit with potential alterations. If it were possible to reach this true ground state and eliminate all matter, energy, radiation, and spacetime curvature, one would be left with the ultimate notion of “physical nothingness.” While a stage for the Universe remains, devoid of actors, script, or scenes, the vast emptiness still provides a backdrop. At its absolute minimum, the cosmic vacuum would yield no energy, work, or particles, yet this still retains elements of “something,” as space, time, and laws persist.

4. Nothingness Beyond the Universe

This scenario is the most radical interpretation, stepping beyond reality—beyond space, time, and the governing laws of physics—to conceptualize a Platonic ideal of nothingness. We can envision the removal of everything imaginable: space, time, and the rules of existence. In this context, physicists struggle to define anything, as this represents pure philosophical nothingness.

This leads to a significant dilemma in physics: how do we comprehend such nothingness? We are forced to consider a state that exists independently of space and time, suggesting that spacetime and the laws governing our known entities could emerge from this hypothesized ideal state.

Regrettably, the meaning of this line of thought remains elusive. It may simply reflect our ability to conceive of concepts beyond our reality, devoid of any substantial connection. Numerous questions arise from this contemplation without clear answers, such as: How can spacetime manifest at a specific point when there’s no “space” or “time”? Is it feasible to imagine something existing “outside” the Universe without space, or consider a “beginning” without time? Where would the governing rules of particle interactions originate?

This final interpretation of nothingness, while seemingly philosophically satisfying, might lack any real significance. It could merely be a logical construct stemming from our limited human understanding.

When discussing nothing, scientists often find themselves at cross-purposes, each believing their definition is the only valid one. However, a consensus is lacking; language is inherently ambiguous, and the concept of nothingness varies significantly across contexts. “Something from nothing” can describe a situation where an entity emerges from a previously nonexistent state, but interpretations of “nothing” differ among individuals.

Each of the four definitions holds validity in its own right, emphasizing the importance of understanding the speaker's particular interpretation of nothingness. Each definition encompasses its scope and relevance, applicable to various physical phenomena, from the genesis of matter to dark energy, cosmic inflation, and the zero-point energy of space. Nevertheless, these concepts are also products of our cognition. While everything we know may have originated from nothing, the challenge lies in grasping how this transformation occurred.