[Paper Review] Now, and the Flow of Time

Richard A. Muller, Shaun Maguire|arXiv (Cornell University)|Jun 25, 2016

Cosmology and Gravitation Theories2 references3 citations

TL;DR

This paper proposes that the flow of time arises from the continuous creation of new spacetime in four dimensions, where the Hubble expansion generates not only new space but also new moments ('nows'). It predicts a measurable time delay in gravitational wave emissions during black hole mergers due to the creation of new spacetime, offering a testable deviation from general relativity via LIGO observations.

ABSTRACT

The progression of time can be understood by assuming that the Hubble expansion takes place in 4 dimensions rather than in 3. The flow of time consists of the continuous creation of new moments, new nows, that accompany the creation of new space. This model suggests a modification to the metric tensor of the vacuum that leads to testable consequences. Two cosmological tests are proposed, but they present both experimental and theoretical problems. A more practical and immediate test is based on a predicted lag in the emergence of gravitational radiation when two black holes merge. In such mergers (as recently observed by the LIGO team), a macroscopic volume (millions of cubic kilometers) of space is created in the region in which the gravitational wave is generated; this one-time creation of new space should be accompanied by the creation of detectable level of new time, resulting in a time delay that could be observed as a growing lag in the emission of the wave as the merger takes place

Motivation & Objective

• To resolve the fundamental asymmetry between space and time, despite their unification in spacetime.
• To address why time flows forward while space does not, challenging the conventional arrow-of-time explanation via entropy.
• To propose a physically testable mechanism for the flow of time rooted in cosmological spacetime creation.
• To identify observable consequences of new time creation during violent spacetime events, such as black hole mergers.
• To provide a falsifiable alternative to entropy-based theories of time's arrow, grounded in general relativity with modified vacuum dynamics.

Proposed method

• Model the universe using a 4D spacetime framework where the Hubble expansion generates new space and time simultaneously.
• Modify the vacuum metric tensor to include a term that produces proper time when spacetime is dynamically disturbed.
• Apply the model to black hole mergers, where large volumes of space are created rapidly, predicting a time lag in gravitational wave emission.
• Use LIGO data to search for deviations in waveforms that could signal a delay due to new time creation.
• Analyze the causal structure of spacetime to explore why new time is created only at the 'end' of time, not uniformly.
• Compare the model with standard general relativity and assess its consistency with known constraints, including gravitational redshift and causality.

Experimental results

Research questions

• RQ1 Can the flow of time be explained by the continuous creation of new spacetime in four dimensions?
• RQ2 Does the creation of new space during black hole mergers lead to a detectable time delay in gravitational wave emission?
• RQ3 Is the asymmetry in the creation of new time (only at the end of time) a physical necessity or a coordinate artifact?
• RQ4 Can the model be distinguished from general relativity through observational tests, particularly with LIGO data?
• RQ5 What would be the implications for causality and free will if time were not continuously created?

Key findings

• The model proposes that new moments ('nows') are created continuously as new space is generated during the Hubble expansion, explaining the flow of time.
• A time delay of approximately 1 millisecond is predicted during black hole mergers due to the creation of new spacetime, based on the volume of space generated.
• The predicted time lag arises because new time is created alongside new space, leading to a measurable delay in the emission of gravitational waves.
• The model suggests that the vacuum metric must include an additional term that generates proper time under dynamic spacetime conditions, beyond standard dark energy.
• The theory implies that time's arrow is not set by entropy or thermodynamics, but by the cosmological creation of spacetime, offering a falsifiable alternative.
• The model predicts that time reversal would only occur in extreme conditions, such as for black holes below 2.4×10¹⁰ kg, where evaporation could outpace cosmological time creation.