Overview updates (quantumlib#5567)

Some small phrasing/style updates to the overview pages.

docs/_book.yaml

@@ -78,6 +78,8 @@ upper_tabs:
         path: /cirq/simulation
       - title: "Noisy Simulation"
         path: /cirq/noisy_simulation
+      - title: "Parameter Sweeps"
+        path: /cirq/params
       - title: "State Histograms"
         path: /cirq/tutorials/state_histograms
 

docs/build/_index.yaml

@@ -7,54 +7,40 @@ landing_page:
     - heading: Build a circuit
       description: At the core of Cirq is the ability to construct quantum circuits. These are the methods and data structures necessary to do so.
     - heading: Circuit construction
-      description: Read these to understand what goes into building a Cirq circuit (estimated reading time one hour).
+      description: The core data structures that compose a circuit and how to use them.
+      options:
+        - cards
       items:
       - heading: Circuits
-        description: The Circuit data structure and how to create them.
+        description: Quantum circuits and how to create them.
         path: /cirq/circuits
-        icon:
-          name: menu_book
       - heading: Qubits
         description: The quantum bit data structure.
         path: /cirq/qubits
-        icon:
-          name: menu_book
       - heading: Gates and Operations
-        description: Quantum Gate and Operation data structures and how they are different.
+        description: Quantum gates to apply to qubits in a circuit.
         path: /cirq/gates
-        icon:
-          name: menu_book
       - heading: Custom gates
-        description: Create your own gates to add to circuits.
+        description: Create your own gates with unitaries or decomposition.
         path: /cirq/custom_gates
-        icon:
-          name: menu_book
       - heading: Import/export circuits
-        description: How to import or export a quantum circuit into/from Cirq.
+        description: Importing or exporting circuits into/out of Cirq.
         path: /cirq/interop
-        icon:
-          name: menu_book
 
-    - heading: Advanced
+    - heading: Advanced construction
       description: More elaborate ways to build quantum circuits.
+      options:
+        - cards
       items:
       - heading: Operators
-        description: Operators, measurements and noise channels.
+        description: Unitary operators, measurements and noise channels.
         path: /cirq/operators
-        icon:
-          name: menu_book
       - heading: Qudits
-        description: Moving from qubits to qutrits and further.
+        description: Qutrits and higher dimensional quantum systems.
         path: /cirq/qudits
-        icon:
-          name: menu_book
       - heading: Protocols
-        description: The magic methods supported by Cirq's classes.
+        description: Magic methods supported by Cirq's classes.
         path: /cirq/protocols
-        icon:
-          name: menu_book
       - heading: Tools ecosystem
         description: External tools for circuit construction.
         path: /cirq/ecosystem
-        icon:
-          name: menu_book

docs/experiments/_index.yaml

@@ -5,41 +5,36 @@ landing_page:
   nav: left
   rows:
     - heading: Experiments using quantum circuits
-      description: This is a collection of algorithms and experiments written in and using Cirq. Some are hosted in Cirq, and some are hosted in ReCirq, a repository for research performed with Cirq.
+      description: This is a collection of algorithms and experiments written in and using Cirq. Some are hosted in the Cirq Github repository, and some are hosted in ReCirq, a repository for research performed with Cirq.
+    - buttons:
+      - label: Cirq Github
+        path: https://github.com/quantumlib/Cirq
+      - label: ReCirq Github
+        path: https://github.com/quantumlib/ReCirq
     - heading: Algorithms in Cirq
-      description: Algorithms and experiments executable with only default Cirq code.
+      description: Algorithms and experiments executable using only default Cirq code.
+      options:
+        - cards
       items:
       - heading: Textbook Algorithms Workshop
         description: A workshop notebook with examples that covers algorithms commonly shown in quantum textbooks.
         path: /cirq/tutorials/educators/textbook_algorithms
-        icon:
-          name: menu_book
       - heading: Shor's Algorithm
         description: The famous integer factorization algorithm by Peter Shor.
         path: /cirq/tutorials/shor
-        icon:
-          name: menu_book
       - heading: Variational Quantum Eigensolver
         description: Compute the ground state of a Hamiltonian using the variational principle.
         path: /cirq/tutorials/variational_algorithm
-        icon:
-          name: menu_book
       - heading: Quantum Walks
         description: The quantum analog of a random walk algorithm.
         path: /cirq/tutorials/quantum_walks
-        icon:
-          name: menu_book
       - heading: Fourier Checking
         description: Demonstrate the separation between quantum and classical computers.
         path: /cirq/tutorials/fourier_checking
-        icon:
-          name: menu_book
       - heading: Hidden Linear Function problem
         description: Show quantum separation with a constant depth solution.
         path: /cirq/tutorials/hidden_linear_function
-        icon:
-          name: menu_book
 
     - heading: ReCirq Experiments
-      description: Research experiments that use additional library code reside in the external ReCirq repository.
+      description: Research experiments that use additional library code that resides in the external ReCirq repository.
     - include: /cirq/experiments/_index_included.yaml

docs/hardware/_index.yaml

@@ -4,116 +4,95 @@ title: Hardware
 landing_page:
   nav: left
   rows:
-    - heading: Run circuits on quantum hardware
-      description: In order to run circuits on a quantum hardware device, Cirq maintains a representation of that device in software that determines if a circuit can be run on it.
+    - heading: Represent a quantum hardware device
+      description: Define the characteristics and constraints of quantum hardware devices, to support running circuits on those devices.
+      options:
+        - cards
       items:
       - heading: Devices
-        description: A data structure to represent the constraints a device imposes on runnable circuits.
+        description: Represent the constraints a device imposes on runnable circuits with the Device class.
         path: /cirq/devices
-        icon:
-          name: menu_book
+
+    - heading: Run a circuit on a hardware device
+      description: Cirq provides interfaces for running your circuits on quantum hardware provided by many different services.
 
     - heading: AQT hardware
-      description: Cirq's interface with Alpine Quantum Technologies hardware
+      description: Cirq's interface with Alpine Quantum Technologies hardware.
+      options:
+        - cards
       items:
       - heading: Access and authentication
         description: How to gain access.
         path: /cirq/aqt/access
-        icon:
-          name: menu_book
       - heading: Getting started with AQT hardware
         description: How to run your first circuit.
         path: /cirq/tutorials/aqt/getting_started
-        icon:
-          name: menu_book
 
     - heading: Azure Quantum
       description: Cirq's interface with Microsoft Azure Quantum services.
+      options:
+        - cards
       items:
       - heading: Access and authentication
         description: How to gain access.
         path: /cirq/azure-quantum/access
-        icon:
-          name: menu_book
       - heading: Getting started with Honeywell on AQT hardware
         description: How to run your first circuit on a Honeywell device.
         path: /cirq/tutorials/azure-quantum/getting_started_honeywell
-        icon:
-          name: menu_book
       - heading: Getting started with IonQ on AQT hardware
         description: How to run your first circuit on an IonQ device.
         path: /cirq/tutorials/azure-quantum/getting_started_ionq
-        icon:
-          name: menu_book
 
     - heading: IonQ hardware
       description: Cirq's interface with IonQ hardware.
+      options:
+        - cards
       items:
       - heading: Access and authentication
         description: How to gain access.
         path: /cirq/ionq/access
-        icon:
-          name: menu_book
       - heading: Getting started with IonQ hardware
         description: How to run your first circuit.
         path: /cirq/tutorials/ionq/getting_started
-        icon:
-          name: menu_book
       - heading: IonQ API Service
         description: Using the IonQ API.
         path: /cirq/ionq/service
-        icon:
-          name: menu_book
       - heading: IonQ API circuits
         description: Writing circuits for the IonQ API.
         path: /cirq/ionq/circuits
-        icon:
-          name: menu_book
       - heading: Running IonQ API jobs
         description: How to run jobs with the IonQ API.
         path: /cirq/ionq/jobs
-        icon:
-          name: menu_book
       - heading: IonQ API calibrations
         description: How to get hardware device calibration data through the IonQ API.
         path: /cirq/ionq/calibrations
-        icon:
-          name: menu_book
 
     - heading: Pasqal hardware
       description: Cirq's interface with Pasqal hardware.
+      options:
+        - cards
       items:
       - heading: Access and authentication
         description: How to gain access.
         path: /cirq/pasqal/access
-        icon:
-          name: menu_book
       - heading: Getting started with Pasqal hardware
         description: How to run your first circuit.
         path: /cirq/tutorials/pasqal/getting_started
-        icon:
-          name: menu_book
       - heading: Pasqal devices
         description: Device objects to specify Pasqal hardware.
         path: /cirq/pasqal/devices
-        icon:
-          name: menu_book
       - heading: Pasqal sampler
         description: Sampler objects to run on Pasqal hardware.
         path: /cirq/pasqal/sampler
-        icon:
-          name: menu_book
 
     - heading: Rigetti hardware
       description: Cirq's interface with Rigetti hardware.
+      options:
+        - cards
       items:
       - heading: Access and authentication
         description: How to gain access.
         path: /cirq/rigetti/access
-        icon:
-          name: menu_book
       - heading: Getting started with Rigetti hardware
         description: How to run your first circuit.
         path: /cirq/tutorials/rigetti/getting_started
-        icon:
-          name: menu_book

docs/noise/_index.yaml

@@ -5,30 +5,26 @@ landing_page:
   nav: left
   rows:
     - heading: Manage noise when running circuits
-      description: Running circuits on real quantum devices means dealing with the noise those devices introduce to the computation. Cirq provides different ways to managing that noise, to improve the reliability of a circuit when run on hardware.
+      description: Running circuits on quantum hardware devices means dealing with the noise those devices introduce to the computation. Cirq provides the following ways of managing that noise, to improve the quality of the measured results.
     - heading: Characterization and compensation
-      description: By first characterizing how much and what kinds of error a device is exhibiting, compensation can be used to improve the reliability of the next run on the device or interpret the results of a previous run more accurately.
+      description: Characterize the error a device is exhibiting, then compensate for that error by changing the circuit or reinterpreting the results.
+      options:
+        - cards
       items:
         - heading: Calibration FAQ
           description: Frequently asked questions about characterization and compensation.
           path: /cirq/tutorials/google/calibration_faq
-          icon:
-            name: menu_book
         - heading: Floquet Calibration
           description: A characterization method using Floquet theory.
           path: /cirq/tutorials/google/floquet_calibration_example
-          icon:
-            name: menu_book
         - heading: Cross Entropy Benchmarking (XEB)
           description: A characterization benchmarking method using cross entropy.
           path: /cirq/qcvv/xeb_theory
-          icon:
-            name: menu_book
     - heading: Visualizing noise
       description: Graphing and plotting methods for visualizing noise.
+      options:
+        - cards
       items:
         - heading: Heatmaps
-          description: Functions to plot noise characteristics across a device.
+          description: Functions to plot noise characteristics across a 2D grid device.
           path: /cirq/tutorials/heatmaps
-          icon:
-            name: menu_book

docs/simulate/_index.yaml

@@ -5,25 +5,19 @@ landing_page:
   nav: left
   rows:
     - heading: Simulate a circuit
-      description: Cirq provides different ways to compute the effects of a quantum circuit, by simulating a quantum computer with a classical one.
+      description: Compute the effects of a quantum circuit, by simulating a quantum computer with a classical one.
+      options:
+        - cards
       items:
       - heading: Exact Simulation
-        description: Simulate a perfect and noiseless quantum computer, as the mathematical theory intended.
+        description: Simulate a perfectly noiseless quantum computer.
         path: /cirq/simulation
-        icon:
-          name: menu_book
       - heading: Noisy Simulation
-        description: Simulate a more realistic quantum computer, subject to error and noise, which affects the accuracy of the results.
+        description: Simulate a more realistic quantum computer, subject to error and noise.
         path: /cirq/noisy_simulation
-        icon:
-          name: menu_book
       - heading: Parameter Sweeps
-        description: Parameterize circuits and execute them for multiple values of the parameters.
+        description: Efficiently evaluate many circuits which only differ in operation parameter values.
         path: /cirq/params
-        icon:
-          name: menu_book
       - heading: State Histograms
         description: Visualize the results of simulation as a histogram over basis states.
         path: /cirq/tutorials/state_histograms
-        icon:
-          name: menu_book

docs/transform/_index.yaml

@@ -5,15 +5,13 @@ landing_page:
   nav: left
   rows:
     - heading: Transform a circuit
-      description: Cirq provides different ways of transforming a provided circuit, which may be necessary to prepare it to run on quantum hardware device, or to improve its reliability on a device.
+      description: Programmatically transform a provided circuit into another one to implement any compilation or optimization process that changes a circuit.
+      options:
+        - cards
       items:
       - heading: Circuit Transformers
-        description: The Transformer class to represent some process to change a supplied circuit.
+        description: The Transformer class and contract to represent some process that changes a supplied circuit.
         path: /cirq/transformers
-        icon:
-          name: menu_book
       - heading: Custom Transformers
         description: Write your own Transformer with decorators, primitives and decompositions.
         path: /cirq/transform/custom_transformers
-        icon:
-          name: menu_book