The tradeoff between process time and error produces an optimal grid size on economic activity which is influenced by the rate of interest. The rate of interest changes the value of time and hence the velocity of money.  1999 Elsevier Science S.A. All rights reserved.

Quantum cryptography is an approach to securing communications by applying the phenomena of quantum physics. Quantum cryptography provides secure communication whose security depends only on the validity of quantum theory. Interesting characteristics of quantum mechanics includes the existence of indivisible quanta and of entangled systems, both of which lie at the root of the quantum cryptogra...

I formulate a search-based asset-pricing model where equity shares and fiat money can be used as means of payment. I characterize a family of optimal stochastic monetary policies. Every policy in this family implements Friedman’s prescription of zero nominal interest rates. Under an optimal policy, equity prices and returns are independent of monetary considerations. I also study a perturbation...

We broadly define liquid assets, or monetary assets, as any asset that can be readily sold in the market and can be held by a number of people in succession before maturity. We ask in what environment is the circulation of liquid assets essential for the smooth running of the economy. By developing a canonical model of a monetary economy (i.e., where the circulation of liquid assets is essentia...

Now that we’ve defined what the quantum circuit model, we can begin to construct interesting quantum circuits and think about interesting quantum algorithms. We will approach this task in basically an historical manner. A few lectures ago we saw Deutsch’s algorithm. Recall that in this algorithm we were able to show that there was a set of black box functions for which we could only solve Deuts...

We develop a systematic approach to quantum probability as a theory of rational betting in quantum gambles. In these games of chance, the agent is betting in advance on the outcomes of several (finitely many) incompatible measurements. One of the measurements is subsequently chosen and performed and the money placed on the other measurements is returned to the agent. We show how the rules of ra...

Unforgeable quantum money tokens were the first invention of information science, but remain technologically challenging as they require memories and/or long distance communication. More recently, virtual 'S-money' introduced. These are generated by cryptography, do not or communication, and yet in principle guarantee many security advantages money. Here, we describe implementations S-money sch...

We give a brief introduction to the Gauge Theory of Arbitrage [1]. Treating a calculation of net present values (NPV) and currencies exchanges as a parallel transport in some fibre bundle, we give geometrical interpretation of the interest rate, exchange rates and prices of securities as a proper connection components. This allows us to map the theory of capital market onto the theory of quanti...