Ward Identities for Scale and Special Conformal Transformations in Inflation

We derive the general Ward identities for scale and special conformal transformations in theories of single field inflation. Our analysis is model independent and based on symmetry considerations alone. The identities we obtain are valid to all orders in the slow roll expansion. For special conformal transformations, the Ward identities include a term which is non-linear in the fields that arises due to a compensating spatial reparametrization. Some observational consequences are also discussed.Comment: 42 Pages. v3: Section on checks of the Ward identities added. The JHEP accepted versio

Constraints from Conformal Symmetry on the Three Point Scalar Correlator in Inflation

Using symmetry considerations, we derive Ward identities which relate the three point function of scalar perturbations produced during inflation to the scalar four point function, in a particular limit. The derivation assumes approximate conformal invariance, and the conditions for the slow roll approximation, but is otherwise model independent. The Ward identities allow us to deduce that the three point function must be suppressed in general, being of the same order of magnitude as in the slow roll model. They also fix the three point function in terms of the four point function, upto one constant which we argue is generically suppressed. Our approach is based on analyzing the wave function of the universe, and the Ward identities arise by imposing the requirements of spatial and time reparametrization invariance on it.Comment: 35 pages; Extra references and comments added, The version published in JHE

Similarities and Learnings from Ancient Literature on Blockchain Consensus and Integrity

In this paper, we have studied how the text of an ancient literature on how their integrity has been preserved for several centuries. Specifically, The Vedas is an ancient literature, which has its text remained preserved without any corruption for thousands of years. As we studied the system that protects the integrity of the text, pronunciation and semantics of the The Vedas, we discovered a number of similarities it has with the current concept of blockchain technology. It is surprising that the notion of de-centralized trust and mathematical encodings have existed since thousands of years in order to protect this work of literature. We have presented our findings and analysis of the similarities. There are also certain technical mechanisms that The Vedic integrity system uses, which can be used to enhance the current digital blockchain platforms in terms of its security and robustness

How Secure Is Your IoT Network?

The proliferation of IoT devices in smart homes, hospitals, and enterprise networks is widespread and continuing to increase in a superlinear manner. With this unprecedented growth, how can one assess the security of an IoT network holistically? In this article, we explore two dimensions of security assessment, using vulnerability information of IoT devices and their underlying components ($\textit{compositional security scores}$) and SIEM logs captured from the communications and operations of such devices in a network ($\textit{dynamic activity metrics}$) to propose the notion of an $\textit{attack circuit}$. These measures are used to evaluate the security of IoT devices and the overall IoT network, demonstrating the effectiveness of attack circuits as practical tools for computing security metrics (exploitability, impact, and risk to confidentiality, integrity, and availability) of heterogeneous networks. We propose methods for generating attack circuits with input/output pairs constructed from CVEs using natural language processing (NLP) and with weights computed using standard security scoring procedures, as well as efficient optimization methods for evaluating attack circuits. Our system provides insight into possible attack paths an adversary may utilize based on their exploitability, impact, or overall risk. We have performed experiments on IoT networks to demonstrate the efficacy of the proposed techniques.Comment: IEEE International Congress on Internet of Thing