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This work contributes towards the development of an efficient and scalable open-source Secure Multi-Party Computation (SMPC) protocol on machines with moderate computational resources. We use the ABY2.0 SMPC protocol implemented on the C++ based MOTION2NX framework for secure convolutional neural network (CNN) inference application with semi-honest security. Our list of contributions are as follows. Firstly, we enhance MOTION2NX by providing a tensorized version of several primitive functions including the Hadamard product, indicator function and argmax function. Secondly, we adapt an existing Helper node algorithm, working in tandem with the ABY2.0 protocol, for efficient convolution computation to reduce execution time and RAM usage. Thirdly, we also present a novel splitting algorithm that divides the computations at each CNN layer into multiple configurable chunks. This novel splitting algorithm, providing significant reduction in RAM usage, is of independent interest and is applicable to general SMPC protocols., Comment: 20 pages, 1 figure. arXiv admin note: text overlap with arXiv:2310.10133

This paper aims to develop an efficient open-source Secure Multi-Party Computation (SMPC) repository, that addresses the issue of practical and scalable implementation of SMPC protocol on machines with moderate computational resources, while aiming to reduce the execution time. We implement the ABY2.0 protocol for SMPC, providing developers with effective tools for building applications on the ABY 2.0 protocol. This article addresses the limitations of the C++ based MOTION2NX framework for secure neural network inference, including memory constraints and operation compatibility issues. Our enhancements include optimizing the memory usage, reducing execution time using a third-party Helper node, and enhancing efficiency while still preserving data privacy. These optimizations enable MNIST dataset inference in just 32 seconds with only 0.2 GB of RAM for a 5-layer neural network. In contrast, the previous baseline implementation required 8.03 GB of RAM and 200 seconds of execution time.

We study service scheduling problems in a slotted system in which agents arrive with service requests according to a Bernoulli process and have to leave within two slots after arrival, service costs are quadratic in service rates, and there are also waiting costs. We consider quadratic waiting costs. We frame the problems as average cost Markov decision processes. While the studied system is a linear system with quadratic costs, it has state dependent control. Moreover, it also possesses a non-standard cost function structure in the case of fixed waiting costs, rendering the optimization problem complex. We characterize optimal policy. We provide an explicit expression showing that the optimal policy is linear in the system state. We also consider systems in which the agents make scheduling decisions for their respective service requests keeping their own cost in view. We consider quadratic waiting costs and frame these scheduling problems as stochastic games. We provide Nash equilibria of this game. To address the issue of unknown system parameters, we propose an algorithm to estimate them. We also bound the cost difference of the actual cost incurred and the cost incurred using estimated parameters., Comment: arXiv admin note: substantial text overlap with arXiv:2110.05148

We study service scheduling problems in a slotted system in which agents arrive with service requests according to a Bernoulli process and have to leave within two slots after arrival, service costs are quadratic in service rates, and there are also waiting costs. We consider fixed waiting costs. We frame the problems as average cost Markov decision processes. While the studied system is a linear system with quadratic costs, it has state dependent control. Moreover, it also possesses a non-standard cost function structure in the case of fixed waiting costs, rendering the optimization problem complex. Here, we characterize optimal policy. We also consider a system in which the agents make scheduling decisions for their respective service requests keeping their own cost in view. We again consider fixed waiting costs and frame this scheduling problem as a stochastic game. Here, we provide Nash equilibrium.

Big data sources provide a significant opportunity for governments and development stakeholders to sense and identify in near real time, economic impacts of shocks on populations at high spatial and temporal resolutions. In this study, we assess the potential of transaction and location based measures obtained from automatic teller machine (ATM) terminals, belonging to a major private sector bank in Indonesia, to sense in near real time, the impacts of shocks across income groups. For each customer and separately for years 2014 and 2015, we model the relationship between aggregate measures of cash withdrawals for each year, total inter-terminal distance traversed by the customer for the specific year and reported customer income group. Results reveal that the model was able to predict the corresponding income groups with 80% accuracy, with high precision and recall values in comparison to the baseline model, across both the years. Shapley values suggest that the total inter-terminal distance traversed by a customer in each year differed significantly between customer income groups. Kruskal-Wallis test further showed that customers in the lower-middle class income group, have significantly high median values of inter-terminal distances traversed (7.21 Kms for 2014 and 2015) in comparison to high (2.55 Kms and 0.66 Kms for years 2014 and 2015), and low (6.47 Kms for 2014 and 2015) income groups. Although no major shocks were noted in 2014 and 2015, our results show that lower-middle class income group customers, exhibit relatively high mobility in comparison to customers in low and high income groups. Additional work is needed to leverage the sensing capabilities of this data to provide insights on, who, where and by how much is the population impacted by a shock to facilitate targeted responses., Comment: Presented at NeurIPS 2020 Workshop on Machine Learning for the Developing World

\begin{abstract} This paper deals with a precise description of the region of {\it zitterbewegung} below the Compton scale and the stochastic nature associated with it. We endeavour to delineate this particular region by means of {\it Ito's calculus} and instigate certain features that are in sharp contrast with conventional physics. Interestingly, our work substantiates that the {\it zitterbewegung region} represents a pre-spacetime region and from therein emerges the notion of our conventional spacetime. Interestingly, this unique region engenders the relativistic and quantum mechanical aspects of spacetime., Comment: 12 pages

In this brief note we point out that in the case of two dimensional crystals like graaphene, there is an interesting anomalous behaviour of Fermions. This could potentially be useful., Comment: 10 pages, latex

In this paper, we endeavour to obtain a modified form of the Foldy-Wouthuysen and Cini-Toushek transformations by resorting to the noncommutative nature of space-time geometry, starting from the Klein-Gordon equation. Also, we obtain a shift in the energy levels due to noncommutativity and from these results a limit for the Lorentz factor in the ultra-relativistic case has been derived in conformity with observations, Comment: 13 pages

2017 observations by Riess and coworkers have indicated that the universe is expanding some seven percent faster than the currently accepted cosmological model described. In this paper we argue that this discrepancy can be eliminated by considering a universe consisting only of matter and dark energy., Comment: 8 pages

Sidharth had shown that gravitation can be reconciled with electromagnetic and other forces if we start from a Landau-Ginzburg phase transition. This is further remarked upon and a unification of all forces of nature is proposed., Comment: 10 pages, IIAMIS-TR 08 2016 No.1

In a recent paper in EPJC January 2016, Faizal, Khalil and Das have proposed time crystals with duration several orders of magnitude greater than Planck scale. We comment on this paper and shed further light on this aspect., Comment: 5 pages

We consider a formulation using Kerr-Newman metric which leads to an extra force hitherto unknown and we justify that this is the "fifth Force" that is being sought after., Comment: 13 pages. arXiv admin note: text overlap with arXiv:1106.6103

In this paper we endeavour to find a connection between the non-commutative nature of space time and the {\it zero point field}. We observe that extra effects come into play when we take into account the Compton scale effects in such a space-time and the electromagnetic field tensor and the current density get modified. This defines an underlying connection between non-commutativity and the {\it zero point field}., Comment: 6 pages

Corda, Mosquera Cuesta and Lorduy Gomez have shown that spherically symmetric stationary states can be used as a model for galaxies in the framework of the linearized R^2 gravity. Those states could represent a partial solution to the Dark Matter Problem. Here we discuss an improvement of this work. In fact, as the star density is a functional of the invariants of the associated Vlasov equation, we show that any of these invariants is in its turn a functional of the local energy and the angular momentum. As a consequence, the star density depends only on these two integrals of the Vlasov system. This result is known as the "Jeans theorem". In addition, we find an analogous of the historical Tolman- Oppenheimer-Volkov equation for the system considered in this paper. For the sake of completeness, in the final Section of the paper we consider two additional models which argue that Dark Matter could not be an essential element., Comment: Comments: 15 pages, the results of arXiv:1105.0147 have been partially reviewed. Final version matching the one published in the Adv. High En. Phys. Special Issue "Classical and Quantum Gravity and Its Applications" Edited by S. Hossein Hendi and others

In this paper we consider solutions of the Dirac equation at ultra high energies. The study provides new insights including features overlooked thus far and also new ramifications., Comment: 13 pages latex; Invited talk at FFP13, November 2013

Neutrinos are the weirdest of elementary particles, nearly massless and chiral. They oscillate between flavours, furthermore. We try to find a rationale for this maverick behaviour., Comment: 7 pages tex

We revisit the problems of dark energy and dark matter and several models designed to explain them, leading to the hypothetical fifth force in the light of some latest findings., Comment: 37 pages, latex, New Advances in Physic (91), 2013. arXiv admin note: substantial text overlap with arXiv:physics/0411224, arXiv:1011.4575, arXiv:physics/0609254, arXiv:1112.1773, arXiv:0803.4302, arXiv:0902.3342, arXiv:1201.0915, arXiv:physics/0608222, arXiv:physics/0403034, arXiv:physics/0404024, arXiv:0905.3896, arXiv:physics/0110040, arXiv:1106.6103

We propose a new approach to practical two-party computation secure against an active adversary. All prior practical protocols were based on Yao's garbled circuits. We use an OT-based approach and get efficiency via OT extension in the random oracle model. To get a practical protocol we introduce a number of novel techniques for relating the outputs and inputs of OTs in a larger construction. We also report on an implementation of this approach, that shows that our protocol is more efficient than any previous one: For big enough circuits, we can evaluate more than 20000 Boolean gates per second. As an example, evaluating one oblivious AES encryption (~34000 gates) takes 64 seconds, but when repeating the task 27 times it only takes less than 3 seconds per instance.

As 2011 ended, two results stood out which seemed to go against twentieth century ideas. The first was the OPERA superluminal neutrino observation contradicting Special Relativity. The second was lack of a definitive appearance of the Higgs Boson. While both these hopefully will be decided by the end of 2012, we investigate a single mechanism that explains both these anomalies., Comment: 10 pages; Based on the Bhagavantam Memorial Lecture, A.P.Academy of Sciences

Though the concept of a dark energy driven accelerating universe was introduced by the author in 1997, to date dark energy itself, as described below has remained a paradigm. A model for the cosmological constant is suggested., Comment: 12 pages latex. From Proc. FFP11, Paris, AIP, N.Y. arXiv admin note: substantial text overlap with arXiv:physics/0411224, arXiv:0803.4302

Some seventy five years ago, the concept of dark matter was introduced by Zwicky to explain the anomaly of galactic rotation curves, though there is no clue to its identity or existence to date. In 1997, the author had introduced a model of the universe which went diametrically opposite to the existing paradigm which was a dark matter assisted decelarating universe. The new model introduces a dark energy driven accelarating universe though with a small cosmological constant. The very next year this new picture was confirmed by the Supernova observations of Perlmutter, Riess and Schmidt. These astronomers got the 2011 Nobel Prize for this dramatic observation. All this is discussed briefly, including the fact that dark energy may obviate the need for dark matter., Comment: 14 pages, tex; Invited talk in special session of FFP12 in Udine, Italy to mark the 2011 Nobel Prize in physics

Invoking a model of an elementary particle as a collection of ultra relativistic transient particles we show that it is possible to recover the energy of the particle by bombarding it with monochromatic high-energy radiation., Comment: 18 pages, invited talk at 12th Front.Fund.Phys. Symposium, University of Udine, 2011

We revisit considerations of temporal order in relativistic effects, taking into account Heisenberg's Uncertainty Principle. We then use a formulation of relativistic Quantum Mechanical equations given by Feshbach and Villars to exhibit novel particle antiparticle effects., Comment: 9 pages, latex

We develop an iso spin like formulation with particles and their anti particle counterparts. This leads to a new shortlived interaction between them, valid at very high energies and mediated by massive particles. We point out that evidence for this is already suggested by the very recent observations by the CDF team at Fermi Lab., Comment: 8 pages latex; Int.J.Mod.Phys E, 2011

We review some recent studies of particle-antiparticle behaviour (including proton-antiproton) at high energies, which suggest a new short lived interaction between them. We then examine the latest evidence from the CDF team at Fermi Lab which bears out this result to a little above $3 \sigma$ level., Comment: 11 pages; latex

We revisit the negative energy solutions of the Dirac equation, which become relevant at very high energies and study several symmetries which follow therefrom. The consequences are briefly examined., Comment: 11 pages, Latex

We reexamine the behaviour of particles at Ultra Highe energies in the context of the fact that the LHC has already touched an energy of $7 TeV$ and is likely to attain $14 TeV$ by 2013/2014.Consequences like a possible new shortlived interaction within the Compton scale are discussed., Comment: 12 pages. arXiv admin note: text overlap with arXiv:1008.2491

We revisit the problem of a mechanism that generates the mass spectrum of elementary particles. This has vexed physicists for several decades now. In this connection we deduce a formula that gives the masses of all known elementary particles, even though other quantum numbers are suppressed. These considerations become important in view of the LHC which is expected to attain 14 TeV by 2013., Comment: 10 pages latex

The twentieth century has thrown up exotic concepts -- dark matter, gravity waves, Higgs Bosons, Magnetic Monopoles and so on. The sad truth is that even after several decades, these remain elusive to observation and experiment. Some are now questioning these conjectures. Their verification has become a matter more of hope than conviction. We will examine some alternatives in the light of the above pointing out that, on the other hand, an extra neutrino, recently predicted by the author may have just been discovered., Comment: 23 pages, Invited talk at Frontiers of Nuclear Physics International Conference, Department of Atomic Energy, Govt. of India

We consider the problem of distance between two particles in the universe, where space is taken to be Liebnizian rather than Newtonian, this being the present day approach. We then argue that with latest inputs from physics, it is possible to define such a distance in a topological sense., Comment: 6 pages Latex

The LHC in Geneva is already operating at a total energy of $7 TeV$ and hopefully after a pause in 2012, it will attain its full capacity of $14 TeV$ in 2013. These are the highest energies achieved todate in any accelerator. It is against this backdrop that it is worthwhile to revisit very high energy collisions of Fermions (Cf. also \cite{bgspp}). We will in fact examine their behaviour at such energies., Comment: 11 pages -- expanded new version

We consider two problems that have vexed physicists for several decades -- dark matter and the cosmological constant. The problem has been that the former has not been detected while the latter gives a far higher value than detected by observation. We argue that a time varying gravitational constant obviates the former problem, while the latter problem can be circumvented by considering the average density of the universe., Comment: 11 pages latex

Numerous observations and studies suggest that the universe has some sort of overall rotation. We consider this matter and provide a new angle., Comment: 8 pages

Modifications in the energy momentum dispersion laws due to a noncommutative geometry, have been considered in recent years. We examine the oscillations of extended objects in this perspective and find that there is now a "generation" of energy., Comment: 13 pages Latex

Astronomical observations were used as a marker for time and the Calendar from ancient times. A more subtle calibration of epochs is thrown up by an observation of the position of the solstices and equinoxes, because these points shift in the sky with the years resulting in the gradual shift of celestial longitudes $\lambda$. Chronology based on such observations however needs to be backed up by hard evidence. We match both to take us back to $10,000$ B.C., the epi-paleolithic period, and the beginning of civilization itself., Comment: 18 pages, Latex

We consider a model for an underpinning of the universe: there are oscillators at the Planck scale in the background dark energy. Starting from a coherent array of such oscillators it is possible to get a description from elementary particles to Black Holes including the usual Hawking-Beckenstein theory. There is also a description of Gravitation in the above model which points to a unified description with electromagnetism., Comment: 18 pages latex; talk at the Max Born Symposium 2009, Wroclaw

We consider the behavior of the particles at ultra relativistic energies, for both the Klein-Gordon and Dirac equations. We observe that the usual description is valid for energies such that we are outside the particle's Compton wavelength. For higher energies however, both the Klein-Gordon and Dirac equations get modified and this leads to some new effects for the particles, including the appearance of anti particles with a slightly different energy., Comment: 9 pages tex

Chirality or the property that distinguishes lefthandedness from righthandedness is an important aspect of the universe, starting from neutrinos, which are lefthanded. Fifteen years ago the author had proposed that life on the earth was formed through a dual process -- several key ingredients being transported from outer space to the earth by comets or meteorites and these in turn interacting with compounds already cooked up in the earth's seas. Several recent observations point to the fact that the amino acids brought out to the earth by meteorites are lefthanded, as in terrestrial life forms. Experiments in the laboratory however throw up equal numbers of lefthanded and righthanded amino acids, what are called racemic mixtures. Not only would the latest observations endorse this dual mode theory of the origin of life, but on the other hand it would point to the key trigger for life processes itself. This is because racemic mixtures are not optically active, unlike the handed or chiral constituents. It is this activity of harnessing solar radiation and converting it into chemical energy, and storing this in the sugar bonds, as in photosynthesis, that characterizes life., Comment: 7 pages Latex

The author's work over the past years has indicated that the photon has a small mass $\sim 10^{-33}eV$. Recent observations from three different viewpoints -- the time lag in cosmic gamma rays with different frequencies, the observation of the spectra of blazars and an analysis of the CMB power supression from the WMAP data -- all vindicate this conclusion and remarkably, the same value., Comment: 8 pages tex

We consider a model for an underpinning of the universe: there are oscillators at the Planck scale in the background dark energy. Starting from a coherent array of such oscillators it is possible to get a description from elementary particles to Black Holes including the usual Hawking-Beckenstein theory. There is also a description of Gravitation in the above model which points to a unified description with electromagnetism., Comment: 9 pages latex; Talk at the Max Born Symposium, Wroclaw, 2009

In the theory of the Dirac equation and in the standard model, the neutrino is massless. Both these theories use Lorentz invariance. In modern approaches however, spacetime is no longer smooth, and this modifies special relativity. We show how such a modification throws up the mass of the (electron) neutrino., Comment: 14 pages, latex

The LHC is expected to resume later this year. Though results at the Tevatron make it more difficult for the LHC to pick out Higgs bosons, there are other results which are expected. Some of these are surveyed here., Comment: 6 pages latex

In this paper we show how it is possible to obtain mass generation in the context of non Abelian gauge field theory, using a non commutative spacetime. This is further confirmed by the modified dispersion relation that results from such a geometry., Comment: 8 pages; latex; Invited talk at Physics 2009

A fundamental spacetime scale in the universe leads to noncommutative spacetime and thence to a modified energy - momentum dispersion relation or equivalently to a modification of Lorentz symmetry as shown by the author and others. This latter consideration has also been used by some scholars though based on purely phenomenological models that have been suggested by the observation of Ultra High Energy Cosmic Rays. On the other hand a parallel development has been the proposal of a small but non zero photon mass by some scholars including the author, such a mass being within experimentally allowable limits. This too leads to a small violation of Lorentz symmetry observable in principle in very high energy gamma rays, as in fact is claimed. We show in this paper that the latter mechanism in fact follows from the former, thus unifying two apparently different approaches., Comment: 9 pages tex

We briefly review two concepts of time - the usual time associated with "being" and more recent ideas, answering to the description of "becoming". The approximation involved in the former is examined. Finally we argue that it is (unpredictable) fluctuations that underlie time., Comment: 16 pages, latex

In the light of recent developments in Dark Energy, we consider the electron in a such a background field and show that at the Compton wavelength the electron is stable, in that the Cassini inward pressure exactly counterbalances the outward Coulomb repulsive pressure thus answering a problem of the earlier electron theory., Comment: 11 pages, tex

In May 2008 the long awaited NASA Satellite, GLAST was launched, which will study cosmic gamma rays. In August 2008, it is expected that the CERN's Large Hadron Collidor (LHC) will finally become operationized. This is found to unwield several new particles. All this has the potential of opening the frontier of a New Physics., Comment: 7 pages latex

The Dirac wave equation for the electron soon lead to the recognition of the Zitterbewegung. This was studied both by Schrodinger and Dirac. Later there were further elegant and sometimes dissenting insights, from different authors. We briefly review some of these developments. However in more recent times with dark energy and noncommutative spacetime coming to centre stage, the earlier studies of Zitterbewegung become questionable., Comment: 14 pages; latex

We argue that the material inside Neutron stars behaves anomalously with fractal statistics and that in principle, we could induce mini Neutron stars, with the release of energy., Comment: To appear in Chaos, Solitons and Fractals

In this paper, we argue that the background Zero Point Field, induces an oscillatory motion which we identify with zitterbewegung. We deduce that this is the origin of inertial mass, Comment: 9 pages, tex