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Updated: Aug 11, 2026
08:56
Clinical Assessment of Spatiotemporal Gait Parameters in Patients and Older Adults
Published on: November 7, 2014
[Physical time and personal biological time in gerontologic research]
Zeitschrift Fur Gerontologie
|March 1, 1989
Summary
A new logarithmic time scale, tau-time, is proposed alongside reversible physical time. This irreversible tau-time, linked to organismal growth and vitality, divides a lifespan into four equal stages, mirroring physical entropy.
Area of Science:
- Biophysics
- Theoretical Biology
- Chronobiology
Context:
- The standard model of physics utilizes a reversible time parameter.
- Biological systems exhibit irreversible processes related to aging and development.
Purpose:
- To introduce a novel, irreversible time parameter, tau-time, for biological systems.
- To establish an analogy between tau-time and physical entropy.
Summary:
- Proposes an irreversible, logarithmic tau-time, distinct from reversible physical time.
- Tau-time quantifies organismal growth, vitality, and reliability.
- Divides an organism's lifespan into four approximately equal stages based on tau-time.
- Highlights a conceptual link between tau-time and the principles of physical entropy.
Impact:
- Offers a new framework for analyzing biological aging and lifespan.
- Provides a potential quantitative measure for organismal health and reliability.
- May bridge the gap between physical laws and biological processes.
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