Voyage Through the Cosmos Lecture Series
ABSTRACTS
John H. Schwarz
Theoretical Physicist, Caltech, USA
Title: String theory in the 20th century: A Personal Perspective
Abstract:
String theories, first developed in the late 1960s, are theories based on one-dimensional objects called strings. This was a radical departure from all previous particle physics theories, which are based on point particles. At the time, the goal was to formulate a theory of the strong nuclear force. However, the correct theory of the strong nuclear force, which is based on point particles, was discovered in 1973. Therefore, almost everyone stopped working on string theory at that time. My collaborators and I continued studying string theory, because we realized that it necessarily incorporates gravity, and that it might provide the correct framework for a unified quantum theory of all fundamental forces. It took a decade of development before this proposal achieved widespread acceptance. Much more has been learned since then, and string theory is mainstream science today.
Andrei D. Linde
Stanford University, USA
Title: Universe or Multiverse?
Abstract:
Cosmological observations show that the universe is remarkably uniform on the largest scales accessible to our telescopes. The inflationary theory offers the most compelling theoretical explanation for this uniformity. Over the last 45 years, many predictions of this theory have been confirmed by cosmological observations. Rather paradoxically, this theory, explaining the uniformity of our part of the universe, predicts that on extremely large scales, much greater than what we can see now, the world may look totally different. Instead of being a single spherically symmetric balloon, our universe may look like a “multiverse,” a collection of many different exponentially large balloons (“universes”) with different laws of low-energy physics operating in each. The new cosmological paradigm, supported by developments in string theory, alters standard views of the universe’s origin and global structure, as well as of our place in the world.
Timothy E. Eastman
(Formerly) Geophysical Institute,
University of Alaska, USA
Title: Plasma Cosmology
Abstract:
Scientists using a plasma cosmology model successfully predicted early in 2022 (in advance of first observations) the existence of fully-formed massive galaxies, similar to local galaxies, at very high redshift as observed by the James Webb Space Telescope. Further, instead of interpreting redshift in terms of cosmic expansion, recent quantum spectroscopy research indicates that observed levels of redshift will necessarily arise from coherent photon scattering through dilute intergalactic electron plasma. Together these recent developments indicate that the universe may be of indefinite age with timescales sufficient to enable galactic evolution, and observed cosmic structures at multiple scale lengths, through both gravity, and electromagnetism and plasma processes. Such a plasma cosmology approach is capable of explaining essentially all known cosmological observations from first principals without the use of ad hoc assumptions such as cosmic expansion, inflation, dark matter, or dark energy.
Mario Livio
(Formerly) Space Telescope Science Institute, Maryland, USA
Title: Is Earth Exceptional?
Abstract:
The questions “How did life on Earth begin?” and “Are we alone in the universe?” are arguably two of the most intriguing in science. While until recently these questions tended to be relegated to the “too difficult” box, the attempts to answer them have now become extraordinarily vibrant and dynamic frontiers of science. I will examine how using knowledge acquired through ingenious chemical experimentation, geological studies, advanced astronomical observations, and imaginative theorizing researchers have managed to delineate a plausible pathway leading from the formation of the Earth to the appearance of the early biological cells. I will also draw on astounding findings of astronomers and astrobiologists in the last three decades —discoveries that have brought us to the verge of being able to detect extraterrestrial life.
Wendy L. Freedman
University of Chicago, USA
Title: Is There Something Missing From Our Current Understanding of the Cosmos?
Abstract:
For nearly a century following the discovery of the expansion of the universe by Edwin Hubble in 1929, astronomers and cosmologists have made great strides in understanding the origin, evolution and composition of the universe. Yet, recently cracks have begun to appear in our standard model of cosmology, one of those stemming from the measurement of Hubble’s constant, the current expansion rate of the universe. Professor Freedman will follow this history and describe recent measurements from the Hubble and James Webb Space Telescopes that may be indicating that something is missing from our current understanding of the cosmos.
Louis Marmet
York University, Canada
Title: An Optical Illusion at the Crossroads of Cosmological Models
Abstract:
In recent decades, high-accuracy astrophysical data extending to high redshifts has revealed significant inconsistencies and gaps within Concordance Cosmology. Notably, the Hubble tension and the observation of mature galaxies at redshifts beyond z = 10 call for a re-evaluation of the foundations of the Standard Cosmological Model and its observational aspects. I will explore limitations of the scientific method and compare two contrasting cosmologies to illustrate how an optical illusion can profoundly alter our understanding of the universe. I aim to show how my personal worldview offers a compelling avenue for research by briefly describing the current status of my work and my future aspirations in understanding the universe.
Topics: Observation and interpretation, redshift, and cosmology
David Dilworth
(Formerly) US Naval Postgraduate School,
California, USA
Title: Bubbles and Voids versus Fancies – Oh My !
Abstract:
Embracing Unlimited Inspiration — Tempered by Carefully Limited Hypotheses & Calm Logic We are blessed & overwhelmed with a daily avalanche of new astrophysics data. We need Inspiration to solve cosmology puzzles, but in the face of abundance our imagination must be tempered with Calm Logic – or we step outside the boundaries of science.
Logical Fallibilism – My Claims could be Wrong
Fallibilism asserts that all physical Scientific theories or interpretations are Indefinite, Provisional, or Tentative, yet that seems forgotten by so many mathematicians who have commandeered Cosmology.
David will illuminate pros and cons of leading Cosmology Models and Theories. You might be in for a few surprises.
Avi Loeb
Harvard University, USA
Title: Searching for Extraterrestrial Technological Artifacts Near Earth
Abstract:
Over the past decade, the first four interstellar objects were discovered. They include the interstellar meteor, IM1, detected on January 8, 2014, `Oumuamua detected on October 19, 2017, Borisov detected on August 29, 2019 and 3I/ATLAS detected on July 1, 2025. Among these, the second and fourth appeared anomalous relative to known solar-system rocks whereas the third appeared to be a familiar comet. IM1 exhibited the highest material strength among all meteorites in the CNEOS catalog of NASA. In June 2023 we recovered 850 spherules from the Pacific Ocean site IM1. A tenth of these submillimeter meteoritic spherules displayed a unique chemical composition, different from familiar solar system materials.
`Oumuamua featured a flat shape and non-gravitational acceleration with no detectable cometary evaporation. 3I/ATLAS has 13 anomalies, including a trajectory aligned to within 5 degrees of the ecliptic plane. Currently, new Galileo Project Observatories are monitoring millions of objects near Earth in the infrared, optical, radio and audio and analyzing their nature with machine-learning software. Forthcoming data from the Rubin Observatory in Chile will offer additional clues on the nature of interstellar objects. Is space trash from extraterrestrial technological civilizations lurking among the natural interstellar rocks?
Luke A. Barnes
Western Sydney University, Australia
Title: A Fortunate Universe – Life in a Finely Tuned Cosmos
Abstract:
Over the last 40 years, scientists have uncovered evidence that if the universe had been forged with even slightly different properties, life as we know it – and life as we can imagine it – would be impossible. With small tweaks to the way the universe works, we can erase the periodic table, disintegrate particles and remove all traces of structure in the cosmos. The fine-tuning of the universe for life is a major unsolved problem in the world of physics. I’ll introduce the science, and show how it leads to deep questions about our cosmos.
George F. R. Ellis
University of Cape Town, South Africa
Title: The nature of the Universe: The Big Picture
Abstract:
I will summarise the current scientific understandings of the nature of the universe, together with their limits. I will conclude with some reflections on the issue of whether there is meaning in the universe, and its relation to moral realism.
Paul J. Steinhardt
Princeton University, USA
Title: Time to take the Big Bang out of the Big Bang Theory
Abstract:
The talk will attempt to explain how a cosmological model that begins with a big bang followed by expansion (with or without inflation) cannot explain the observed properties of our universe. What becomes clear, then, is that the problems can be avoided by replacing the big bang with a bounce and replacing inflation with a period of slow contraction. In explaining this, I will point out common misconceptions about cosmology and general relativity that have been holding us back from making progress.
Pankaj S. Joshi
International Center for Space & Cosmology, India
Title: The Story of Black Hole: Life and Death of Massive Stars in the Universe
Abstract:
Einstein’s theory of gravity predicts the existence of Black Holes and Space-time Singularities. The singularities may be hidden within a black hole or visible to faraway observers in the universe; also called naked singularities. These typically arise from the gravitational collapse of massive stars. We discuss the current theoretical and observational efforts to detect these entities. Quantum gravity effects dominate near naked singularities, which we call ‘Quantum Stars’. These potentially offer an exciting opportunity to test quantum theories of gravity or the Unification of Physics. The connection to new observational missions such as the Event Horizon Telescope (EHT), Gravitational Waves, TMT, and others is pointed out, and recent emerging developments are discussed.
Frank J. Tipler
Tulane University, USA
Title: The Universe: Its Beginning, Its End, and The Role of Humanity in Universal History
Abstract:
The Final Anthropic Principal says that in any universe, intelligent life must come into existence and persist until the end of time. Equivalently, in any universe, a universal computer will be constructed. I shall demonstrate that the laws of physics imply the Final Anthropic Principle. I shall show that future life will turn off the Dark Energy, with the universe then collapsing to a final singularity which has no event horizons: an Omega Point singularity. Such an end to the universe has implications for the beginning of the universe. I shall show that the laws of physics require the universe to have begun in a very regular Friedmann isotropic and homogeneous singularity, with the only field present in the early universe being the SU(2)L field of the Standard Model. This field naturally generates only matter, no antimatter, in the early universe. If this field survived to the present day, it would comprise most of the Cosmic Background Radiation, and such a CBR would resolve several observational inconsistences in cosmology, two examples being (1) the existence of ultrahigh energy cosmic rays which pass through the CBR as if it were not there, and (2) the fact that the Sunyaev-Zel’dovich Effect has been observed by both WMAP and PLANCK to be lower than predicted if the CBR were all-photons. A mainly SU(2)L CBR would also allow the Dark Matter to be an oscillation of the Standard Model Higgs field, and I shall show that were such an oscillation to be the Dark Matter, the Hubble Tension would be resolved. If the CBR is indeed mainly the Standard Model SU(2)L field, this fact can be established by direct observation. The IT billionaire Peter Thiel gave me money to build the necessary apparatus to determine what the CBR is composed of, and I shall present the results of the observations in my lecture. Bottom line: the CBR is indeed mainly the Standard Model SU(2)L field. I shall finish my talk by emphasizing what this means for humanity in general: we humans will create our robotic descendants, and in the far future these AGI’s will resurrect us all, never to die again. If the laws of physics be for us, who can be against us?
Tejinder Pal Singh
Ex-Professor, Tata Institute of Fundamental Research (TIFR), Mumbai & Visiting Professor, IUCAA
Title: Quantum Theory, Gravity, and the Cosmos
Abstract:
Our understanding of the universe is limited by how well we understand the laws of quantum mechanics and of gravitation. A key foundational difficulty with the current formulation of quantum theory is that it depends on an external classical time. Recent developments in addressing this problem guide us towards a novel theory of quantum gravity and its unification with particle physics. We also gain some new insights as to how the universe might have begun and how it might end. It appears as if universes are being born and dying all the time! And the underlying substrate from which they emerge and into which they vanish are what we call atoms of spacetime-matter, a substrate which is indistinguishable from pure mathematics!
R. N. Iyengar
Jain University, India
Title: Concept of Physical Time in the Vedas
Abstract:
Vedic texts characterize kāla (Time) to be of two types. First is the abstract; the second is the physical time as related to sun, moon and the stars. This is the mūrta-kāla (phenomenal time) such as nimeṣa, muhūrta, day, night, fortnight, year etc. Maitrāyaṇīya Āraṇyaka Upaniṣat (MAU) declares Sun to be the origin or generator of time, since ahorātra (day-night) based on counting sunrises is the most natural time unit. Additionally, MAU with its abstract perception says that before manifestation of Sun, it was akāla (non-time). The word kāla for physical time is a derivative of the word kalā (part). Hence, kāla denotes that which is related to and made up of digits or parts. Kāla and Akāla are said to be the two forms of the unitary Brahman. In this talk I briefly discuss the how physical time was characterised leading to chandas (meter) and akṣara (syllable) measure.
M S Sriram
Prof. K.V. Sarma Research Foundation, India
Title: Essential Features of Indian Astronomy
Abstract:
There are references to astronomical observations from the Vedic period in India. They were necessarily qualitative, but significant nevertheless. A basic calendar with solar and lunar months, ecliptic etc. in there. In some Jyotiṣa texts of the Vedāṅga period, there are discussions on cosmology and cosmogony: a primordial state of the dark-matter, out of which all creation including the celestial bodies emerged.
Quantitative astronomy as a scientific discipline in India with well defined methods of calculation van be traced to the Vedāṅga Jyotiṣa of Lagadha (around 1250 BC) . This is in the sutra format, or algorithmic in nature. Here, we have a well defined calendar with the Sun and the Moon moving unformly in the stellar background around the Earth. The algorithmic nature continues in the later siddhāntic texts, beginning with the Āryabhaṭīya (499 CE). Now, the Sun, Moon and the planets do not move uniformly around the Earth.To deal with the non-uniform motion, trigonometry was necessary. Modern trigonometry is the Indian version of it, and enabled Indians to describe the motion of the celestial objects, using formulae.
There was a continuous evolution of ideas in the tradition. It also needs to be emphasised that though the siddhāntic astronomy was algorithmic, the rationales for the algorithms, proofs and demonstrations are to found in various commentaries of the texts.
Ofer Lahav
University College London, UK
Title: Is Dark Energy evolving with cosmic time?
Abstract:
After more than a quarter of a century as the standard model of Cosmology, the Λ Cold Dark Matter (ΛCDM) paradigm is increasingly challenged by combinations of observations from galaxy clustering, weak lensing, Type Ia supernovae, and the cosmic microwave background. This talk will critically review recent results from DESI++ and DES++, and contrast the evidence supporting ΛCDM with emerging indications for an evolving dark energy component.
Manoranjan Sinha
IIT Kharagpur, India
Title: Cosmology in Vedic Tradition
Abstract:
Knowledge about the universe is mainly acquired in three ways, i.e. direct perception, inference, and through revelation. The direct perception encompasses the knowledge in the Surya Siddhanta its contemporary astronomy and is just a modeling of what we directly perceive through our eyes. The inference which encompasses the modern cosmology is primarily based on observations through radio telescopes and then images are reconstructed and colored. This has its own limitations as the inference is always not foolproof as it is an inductive way of acquiring knowledge. On the other hand, the knowledge gained through revelation comes from a perfect knowledgeable source and hence considered to be the real picture of the material nature. Already there are many contending hypotheses about the origin of the universe although the balance is more tilted toward Big-Bang. However, existence of the so many contending hypotheses shows that the knowledge gained through inference is changing with time and bound to change in the future also because it is inductive in nature. The current concept of space time itself may not be fundamental as we get hint from the quantum entanglement. It is proposed that a combination of deductive and inductive approach may resolve many of the existing issues in the cosmology. In this lecture, I propose to show that Vedic texts although not a treatise on astronomy mention about the existence of domain where the time ticks at a different rate, not because of relativity, but because of the nature of the domain. In the Vedic texts, time is not only at different scales in different frames, but also is stated to be as a result of working of mind which we feel as a passage of time. Also those in the higher domain can access the lower domain much easily which is not possible vice-versa. This also states that light cannot escape a boundary defined which extends to the higher dimensions. The distance of the sun and its movement given in the Vedic texts are not irrational. This is shown through texts given in Srimad Bhagavatam and compared against the modern view. Various data given about the movement of the sun has not be deciphered yet but some of them are roughly comparable to the modern values.
Dipankar Banerjee
Indian Institute of Space Science and Technology (IIST), India
Title: A Voyage Through Our Heliosphere to study our nearest Star, the Sun
Abstract:
On September 2, 2023, the Indian Space Research Organisation (ISRO) launched Aditya L1, a dedicated space-based solar observatory, utilizing the Polar Satellite Launch Vehicle (PSLV) C57. Aditya L1 successfully entered halo orbit around the Earth-Sun Lagrange point L1 on January 6, 2024. As India’s inaugural dedicated space-based solar observatory, Aditya L1 offers uninterrupted observations of the Sun, enabling the study of its solar atmosphere, solar wind, and space weather phenomena. The observatory is equipped with a combination of four remote sensing instruments and three in-situ instruments. Since its operational commencement, Aditya L1 has provided invaluable data, including the first high-energy X-ray observations of solar flares and comprehensive full-disk images in the near-ultraviolet spectrum. Aditya L1 is a component of a global initiative involving several other major missions currently monitoring the Sun and heliosphere. Notably, the Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission was launched on March 11, 2025. In this presentation, I will delve into the complementary role of Aditya L1 in enhancing the capabilities of recent missions.
Varun Agarwal
Bhaktivedanta Institute, Kolkata, India;
Alumnus, IIT Kanpur
Title: Cosmology and Consciousness: Search for a Complete Story of our Universe
Abstract:
The journey through the universe is awe-inspiring – massive galaxies, numerous planets, stars, amazing clusters. We have come a long way from the time of Kepler and Galileo, trying to decipher our cosmos with simple instruments to modern day advanced space telescopes, as well as highly abstract mathematics and computation. It is a great triumph for humanity and we know our universe much better than before. However, foundational questions about the universe still remain unanswered as centuries before: why are we here? Why this universe? What was there before the beginning of universe? Why there is something than nothing? Why this earth and why do I exist at all? Questions such as these have pushed renowned thinkers and cosmologists of all times to revisit our cosmological conception and ask: Is the picture of universe we have “complete”? Can a story of universe be complete without ‘thoughts’, without ‘mind’ and without ‘consciousness’, the basic tools with which we have been exploring our universe at the first place? This leads to a further bigger question: Can our understanding of universe ever be complete without bringing in mind and consciousness? Leading thinkers of all times have deeply pondered about some of these foundational questions. The present lecture will attempt, bringing in the insights and works of renowned scholars, such as James James, Arthur Eddington, Carl Sagan, Jayant Narlikar, Owen Gingerich, among others, towards a new vision of our universe where consciousness is also a part. This synthesis will not only help to bridge the missing gaps and foundational questions in modern cosmological picture, but also help towards a better humanity, with better minds to handle numerous challenges we face today. The time has come to expand the boundaries of modern cosmology if we want to save our planet and future generations – a shift of mindset from viewing our universe as an objective material element to subjective and friendly perspective to the universe and our planet. Or else the history will repeat – what we have done to our planet, we will do the same to other planets in future as we explore our galaxy and beyond. Universe is vast, and we are very small – it is thus only a humble attempt in the face of magnificent universe we are gifted with.
Vasudeva Rao
Bhaktivedanta Institute, Kolkata, India;
Alumnus, IIT Kanpur
Title: Does Universe have a Purpose?
Abstract:
The inquiry into whether the universe possess a purpose stands as one of the most profound and epistemologically fraught intersections of theoretical physics, cosmology and philosophy of science. Originating in the classical philosophical frameworks of Plato and Aristotle, the notion that the universe exhibits an intrinsic, goal-directed order was considered virtually self-evident and occupied a contentious and fluctuating position in the natural sciences. However, with the advent of scientific revolution that endorses empirical observation focused strictly on material and efficient causation, teleological explanations were dismissed as “specious and shadowy,” and the search for final causes or purpose was subsequently expunged from the physical sciences. Interestingly, the teleological concepts have made a surprising come back, not rooted in mysticism but rather driven by empirical discoveries in observational cosmology, the baffling implications of quantum mechanics, the fine-tuning of fundamental physical constants, the formalized study of complex, non-linear dynamics and Bayesian probability analysis. We investigate necessary conditions for scientifically concluding purpose for the universe and for the scientific community to legitimately entertain the hypothesis that the universe has a purpose. Also, the central challenge for contemporary philosophy of science is no longer the outright dismissal of purpose, but the rigorous epistemological demarcation of it – a philosophical need for reexamination in distinguishing science from non-science and expanding the boundaries of science if necessary. Such demarcation may not only have implications for a purposeful universe but also for some disciplines or fields practiced under science today.