38,709 research outputs found
Indexical Realism by Inter-Agentic Reference
I happen to believe that though human experiences are to be characterized as pluralistic they are all rooted in the one reality. I would assume the thesis of pluralism but how could I maintain my belief in the realism? There are various discussions in favor of realism but they appear to stay within a particular paradigm so to be called “internal realism”. In this paper I would try to justify my belief in the reality by discussing a special use of indexicals. I will argue for my indexical realism by advancing the thesis that indexicals can be used as an inter-agentic referential term.
Three arguments for the thesis will be presented. The first argument derives from a revision of Kaplan-Kvart’s notion of exportation. Their notions of exportation of singular terms can be analyzed as intra-agentic exportation in the context of a single speaker and theirs may be revised so as to be an inter-agentic exportation in the context of two speakers who use the same indexicals. The second is an argument from the notion of causation which is specifically characterized in the context of inter-theoretic reference. I will argue that any two theories may each say “this” in order to refer what is beyond its own theory. Two theories address themselves to ‘this’ same thing though what ‘this’ represents in each theory turn out to be different objects all together. The third argument is an argument which is based on a possibility of natural reference. Reference is used to be taken mostly as a 3-place predicate: Abe refers an object oi with an expression ej. The traditional notion of reference is constructive and anthropocentric. But I would argue that natural reference is a reference that we humans come to recognize among denumerably many objects in natural states: at a moment mi in a natural state there is a referential relation among objects o1, o2, o3, . . , oj, o j+1, . . which interact to each other as agents of information processors. Natural reference is an original reference which is naturally given and to which humans are passive as we derivatively refer it by using ‘this’
Nonlocal quantum information transfer without superluminal signalling and communication
It is a frequent assumption that - via superluminal information transfers -
superluminal signals capable of enabling communication are necessarily
exchanged in any quantum theory that posits hidden superluminal influences.
However, does the presence of hidden superluminal influences automatically
imply superluminal signalling and communication? The non-signalling theorem
mediates the apparent conflict between quantum mechanics and the theory of
special relativity. However, as a 'no-go' theorem there exist two opposing
interpretations of the non-signalling constraint: foundational and operational.
Concerning Bell's theorem, we argue that Bell employed both interpretations at
different times. Bell finally pursued an explicitly operational position on
non-signalling which is often associated with ontological quantum theory, e.g.,
de Broglie-Bohm theory. This position we refer to as "effective
non-signalling". By contrast, associated with orthodox quantum mechanics is the
foundational position referred to here as "axiomatic non-signalling". In search
of a decisive communication-theoretic criterion for differentiating between
"axiomatic" and "effective" non-signalling, we employ the operational framework
offered by Shannon's mathematical theory of communication. We find that an
effective non-signalling theorem represents two sub-theorems, which we call (1)
non-transfer-control (NTC) theorem, and (2) non-signification-control (NSC)
theorem. Employing NTC and NSC theorems, we report that effective, instead of
axiomatic, non-signalling is entirely sufficient for prohibiting nonlocal
communication. An effective non-signalling theorem allows for nonlocal quantum
information transfer yet - at the same time - effectively denies superluminal
signalling and communication.Comment: 21 pages, 5 figures; The article is published with open acces in
Foundations of Physics (2016
Control-theoretic Approach to Communication with Feedback: Fundamental Limits and Code Design
Feedback communication is studied from a control-theoretic perspective,
mapping the communication problem to a control problem in which the control
signal is received through the same noisy channel as in the communication
problem, and the (nonlinear and time-varying) dynamics of the system determine
a subclass of encoders available at the transmitter. The MMSE capacity is
defined to be the supremum exponential decay rate of the mean square decoding
error. This is upper bounded by the information-theoretic feedback capacity,
which is the supremum of the achievable rates. A sufficient condition is
provided under which the upper bound holds with equality. For the special class
of stationary Gaussian channels, a simple application of Bode's integral
formula shows that the feedback capacity, recently characterized by Kim, is
equal to the maximum instability that can be tolerated by the controller under
a given power constraint. Finally, the control mapping is generalized to the
N-sender AWGN multiple access channel. It is shown that Kramer's code for this
channel, which is known to be sum rate optimal in the class of generalized
linear feedback codes, can be obtained by solving a linear quadratic Gaussian
control problem.Comment: Submitted to IEEE Transactions on Automatic Contro
Information theoretic approach to interactive learning
The principles of statistical mechanics and information theory play an
important role in learning and have inspired both theory and the design of
numerous machine learning algorithms. The new aspect in this paper is a focus
on integrating feedback from the learner. A quantitative approach to
interactive learning and adaptive behavior is proposed, integrating model- and
decision-making into one theoretical framework. This paper follows simple
principles by requiring that the observer's world model and action policy
should result in maximal predictive power at minimal complexity. Classes of
optimal action policies and of optimal models are derived from an objective
function that reflects this trade-off between prediction and complexity. The
resulting optimal models then summarize, at different levels of abstraction,
the process's causal organization in the presence of the learner's actions. A
fundamental consequence of the proposed principle is that the learner's optimal
action policies balance exploration and control as an emerging property.
Interestingly, the explorative component is present in the absence of policy
randomness, i.e. in the optimal deterministic behavior. This is a direct result
of requiring maximal predictive power in the presence of feedback.Comment: 6 page
A Learning Theoretic Approach to Energy Harvesting Communication System Optimization
A point-to-point wireless communication system in which the transmitter is
equipped with an energy harvesting device and a rechargeable battery, is
studied. Both the energy and the data arrivals at the transmitter are modeled
as Markov processes. Delay-limited communication is considered assuming that
the underlying channel is block fading with memory, and the instantaneous
channel state information is available at both the transmitter and the
receiver. The expected total transmitted data during the transmitter's
activation time is maximized under three different sets of assumptions
regarding the information available at the transmitter about the underlying
stochastic processes. A learning theoretic approach is introduced, which does
not assume any a priori information on the Markov processes governing the
communication system. In addition, online and offline optimization problems are
studied for the same setting. Full statistical knowledge and causal information
on the realizations of the underlying stochastic processes are assumed in the
online optimization problem, while the offline optimization problem assumes
non-causal knowledge of the realizations in advance. Comparing the optimal
solutions in all three frameworks, the performance loss due to the lack of the
transmitter's information regarding the behaviors of the underlying Markov
processes is quantified
Mutual Information and Minimum Mean-square Error in Gaussian Channels
This paper deals with arbitrarily distributed finite-power input signals
observed through an additive Gaussian noise channel. It shows a new formula
that connects the input-output mutual information and the minimum mean-square
error (MMSE) achievable by optimal estimation of the input given the output.
That is, the derivative of the mutual information (nats) with respect to the
signal-to-noise ratio (SNR) is equal to half the MMSE, regardless of the input
statistics. This relationship holds for both scalar and vector signals, as well
as for discrete-time and continuous-time noncausal MMSE estimation. This
fundamental information-theoretic result has an unexpected consequence in
continuous-time nonlinear estimation: For any input signal with finite power,
the causal filtering MMSE achieved at SNR is equal to the average value of the
noncausal smoothing MMSE achieved with a channel whose signal-to-noise ratio is
chosen uniformly distributed between 0 and SNR
- …