The Universe, Fixity and Flux | Sabine Hossenfelder, Paul Davies and Lee Smolin | IAI

The paragraph discusses the fundamental question of whether the universe is governed by unchanging laws or if these laws are subject to change over time. It highlights the historical context of scientific thought leaning towards static laws for understanding the universe. However, recent investigations into ancient quasar light and distant galaxies challenge this notion, suggesting that universal laws might evolve. The speakers, including theoretical physicists Lee Smolin, Sabina Hossenfelder, and Paul Davies, introduce their perspectives on this central debate, hinting at the possibility of a new framework to understand a dynamic universe.

This paragraph delves into the re-evaluation of fixed universal laws, prompted by new scientific evidence. Paul Davies posits that the concept of fixed laws might be a theological hangover and suggests that the computational view of the universe could introduce flexibility or error into these laws. He also discusses the limitations of applying fixed laws to biological systems and proposes that laws might change with system complexity. Lee Smolin emphasizes the need to explain not just the universe but also the laws themselves, advocating for a dynamic and active role of time in creating events and potentially shaping the laws.

The speakers explore what constitutes a scientific law, noting that these are observed regularities in nature that can be mathematically formulated. Sabina Hossenfelder questions why certain equations are termed 'laws' while others are not, highlighting the arbitrariness in naming. Paul Davies adds that scientific laws are approximations within broader theories and that the quest for a unified 'super law' reflects the movement towards physics unification. Lee Smolin discusses the limitations of laws applied to small subsystems of the universe and suggests that different methodologies may be needed for understanding the universe as a whole.

The paragraph examines the motivations for questioning the immutability of fundamental laws, with Paul Davies referencing the work of John Webb on the fine structure constant and its potential variation over time. This observation challenges the laws of electromagnetism and quantum mechanics. Davies also discusses the limitations of applying fixed laws to biological systems, suggesting that a new conceptual framework may be necessary. Sabina Hossenfelder mentions the tensions in cosmology that hint at a need for a reorganization of the current framework, and Lee Smolin emphasizes the importance of considering time as an active creator of events and laws.

In this paragraph, Lee Smolin elaborates on the idea that universal laws might be emergent properties, with precedence playing a crucial role. He proposes a measure of 'variety' to quantify the difference in viewpoints of events in the universe, which leads to Schrodinger's equation under certain conditions. Smolin suggests that this approach could provide a new kind of law applicable to the entire universe, challenging the traditional view of time and the emergence of laws from lawlessness.

The speakers discuss the implications of potential changes in universal laws for scientific practice. Lee Smolin suggests that such changes would require a radical shift in our understanding, particularly in relation to quantum mechanics and the nature of time. Paul Davies raises the question of whether the traditional scientific pursuit of universal truths might need to be reevaluated. Sabina Hossenfelder discusses the utility of the multiverse concept, suggesting that while it's a useful thought experiment, it may not be directly applicable to explaining observations in our universe.

The final paragraph synthesizes the discussion, highlighting the potential insights into the nature of time and universal laws. Lee Smolin emphasizes the importance of considering time as dynamic and irreversible, which has implications for understanding the reversibility of laws at intermediate scales. The speakers also ponder the inevitability of the current laws, questioning whether contingent evolution could have led to different outcomes. The conversation concludes with an acknowledgment of the value in using biology as an example for understanding physical concepts.